user-1: Want references/excerpts and inference pertaining to the references & etymology for the designation[s] of "Emptiness" as it is used in the Pali Sutta.

user13709: Transcending form, leaving stress behind, perception shifts to space:

MN121:6.1: Furthermore, a mendicant—ignoring the perception of wilderness and the perception of earth—focuses on the oneness dependent on the perception of the dimension of infinite space.

Transcending space, leaving stress behind, perception shifts to consciousness:

MN121:7.1: Furthermore, a mendicant—ignoring the perception of earth and the perception of the dimension of infinite space—focuses on the oneness dependent on the perception of the dimension of infinite consciousness.

Transcending consciousness, leaving stress behind, perception shifts to nothingness:

MN121:8.1: Furthermore, a mendicant—ignoring the perception of the dimension of infinite space and the perception of the dimension of infinite consciousness—focuses on the oneness dependent on the perception of the dimension of nothingness.

Continuing thus, beyond signs, beyond even the signless, leaving stress behind, perception shifts to emptiness, without defilements:

MN121:12.4: They understand: ‘This field of perception is empty of the perception of the defilements of sensuality, desire to be reborn, and ignorance.
MN121:12.5: There is only this that is not emptiness, namely that associated with the six sense fields dependent on this body and conditioned by life.’
MN121:12.6: And so they regard it as empty of what is not there, but as to what remains they understand that it is present.
MN121:12.7: That’s how emptiness is born in them—genuine, undistorted, and pure.

That is a summary of how emptiness is understood per MN121. Everything else is simply stressful commentary.

user471: This is well explained by Ven. Thanissaro in his commentary to MN 122:

This sutta gives many valuable lessons on practical issues surrounding
the attempt to develop an internal meditative dwelling of emptiness,
to maintain it, and to see it through to Awakening. Some of these
issues include the need for seclusion as a conducive setting for the
practice, types of conversation and thinking that are beneficial and
harmful for the practice, the dangers of being distracted by visitors,
and the proper attitude to have toward one's teacher. However, for an
explanation of emptiness in and of itself, it's necessary to look
elsewhere in the Canon.
There you find emptiness approached from three perspectives, treating
it (1) as a meditative dwelling, (2) as an attribute of objects, and
(3) as a type of awareness-release. The first approach is obviously
the most immediately relevant to the discussion in this sutta, but in
fact all three approaches play a role here.
Emptiness as a meditative dwelling is most fully discussed in MN 121.
Essentially, it boils down to the ability to center the mind in a
particular mode of perception, to maintain it there, and then to
notice the absence and presence of disturbance within that mode. The
process starts with perceptions of one's external surroundings —
village, wilderness, the earth property — and then moves internally to
the four formless states, the "themeless concentration of awareness,"
and finally to release from all mental fermentation. Each step is
compared to the one preceding it to see how its more refined
perception engenders less disturbance. For instance, if you move from
a perception of the wilderness to a perception of earth, the first
step is to settle and "indulge" in that perception. Then you notice
what types of disturbance have been abandoned in the move from the
perception of wilderness to the perception of earth — for example, all
thought of the dangers of wilderness are gone — and then to see what
disturbances remain based on the latter perception. Then you abandon
the perception causing those disturbances and move on to a more
refined level of perception. This process is pursued until it arrives
at the "themeless concentration of awareness." When noting that even
this refined level of concentration is fabricated, inconstant, and
subject to cessation, one gains total release from all mental
fermentations and the disturbances that would arise based on them.
This is the level of emptiness that is "superior and unsurpassed," and
is apparently what the Buddha is referring to in this sutta when he
says that by "not attending to any themes, he enters & remains in
internal emptiness."
Notice that in every step along the way of this process, the emptiness
is the lack of disturbance experienced in a particular mind state.
This means that the mind state is to be perceived simply as an example
of the presence and absence of stress. In other words, emptiness in
this sense relates directly to the second of the three characteristics
— stress or suffering. The pursuit of this emptiness relates to the
four noble truths, as it looks for the causes of stress and uses
tranquility together with insight to abandon those causes in a quest
to put a total end to suffering.
Emptiness in its second meaning, as an attribute of objects, is most
fully discussed in SN 35.85. That sutta describes emptiness as meaning
the lack of self or anything pertaining to a self in the internal and
external sense media. Whatever sense of self that may surround these
objects is not inherent in them, and is instead simply the result of
one's own penchant for "I-making" and "my-making." Seeing the
artificiality of "I-making" and "my-making" in this way helps lead to
a sense of disenchantment with these "makings," thus helping to
abandon any clinging associated with them.
Thus emptiness in this sense relates directly to the third of the
three characteristics: not-self. However, just as the three
characteristics are not radically separate from one another —
everything stressful is for that reason not-self — the practical
application of this sense of emptiness is not radically different from
the first. As SN 12.15 points out, when one no longer latches onto any
idea of "my self," one sees phenomena within and without simply as
examples of stress arising and passing away. To practice meditation
from this perspective — seeing each state of concentration as an
example of stress arising and passing away — is to develop emptiness
as a meditative dwelling.
Emptiness in its third meaning, as a type of awareness-release, is an
application of emptiness in its second. MN 43 describes this state of
concentration as follows: "There is the case where a monk — having
gone into the wilderness, to the root of a tree, or into an empty
dwelling — considers this: 'This is empty of self or of anything
pertaining to self.'" It adds that this awareness-release is different
from the awareness-release that results when one doesn't attend to any
themes. Thus this state of concentration cannot be entirely equated
with the emptiness as a meditative dwelling mentioned in this sutta.
MN 106 further adds that if one frequently abides in the emptiness
awareness-release, one may either attain the dimension of nothingness
— one of the formless states — or be committed to the discernment that
will lead to Awakening. The first of these two alternatives is another
way in which emptiness as an awareness-release differs from emptiness
as a meditative dwelling as defined in MN 121. However, because the
standard definition of discernment is seeing phenomena in terms of the
four noble truths, the second alternative — being committed to
discernment — would apparently follow the same pattern suggested by SN
12.15, above. In other words, as one no longer perceives phenomena in terms of self, one tends to view them simply as examples of stress
arising and passing away. So, again, this third meaning of emptiness,
like the second, eventually leads in practice back to the first. As MN
43 notes, when one attains full awakening, the themeless
awareness-release and the emptiness awareness-release come to differ
only in name, and not in actuality.
In reading the following sutta, you will notice that the various
meanings of emptiness will fit some contexts better than others.
Still, it is important to remember that in the course of practice, all
three meanings are related and all will inevitably play a role in
Awakening.


-1: <p>Want references/excerpts and inference pertaining to the references &amp; etymology for the designation[s] of &quot;Emptiness&quot; as it is used in the Pali Sutta.</p>
 13709: <p>Transcending form, leaving stress behind, perception shifts to space:</p>
<blockquote>
<p><a href="https://suttacentral.net/mn121/en/sujato#mn121:6.1" rel="nofollow noreferrer">MN121:6.1</a>: Furthermore, a mendicant—ignoring the perception of wilderness and the perception of earth—focuses on the oneness dependent on the perception of the dimension of infinite space.</p>
</blockquote>
<p>Transcending space, leaving stress behind, perception shifts to consciousness:</p>
<blockquote>
<p><a href="https://suttacentral.net/mn121/en/sujato#mn121:7.1" rel="nofollow noreferrer">MN121:7.1</a>: Furthermore, a mendicant—ignoring the perception of earth and the perception of the dimension of infinite space—focuses on the oneness dependent on the perception of the dimension of infinite consciousness.</p>
</blockquote>
<p>Transcending consciousness, leaving stress behind, perception shifts to nothingness:</p>
<blockquote>
<p><a href="https://suttacentral.net/mn121/en/sujato#mn121:8.1" rel="nofollow noreferrer">MN121:8.1</a>: Furthermore, a mendicant—ignoring the perception of the dimension of infinite space and the perception of the dimension of infinite consciousness—focuses on the oneness dependent on the perception of the dimension of nothingness.</p>
</blockquote>
<p>Continuing thus, beyond signs, beyond even the signless, leaving stress behind, perception shifts to emptiness, without defilements:</p>
<blockquote>
<p><a href="https://suttacentral.net/mn121/en/sujato#mn121:12.4" rel="nofollow noreferrer">MN121:12.4</a>: <strong>They understand: ‘This field of perception is empty of the perception of the defilements of sensuality, desire to be reborn, and ignorance.</strong><br />
<a href="https://suttacentral.net/mn121/en/sujato#mn121:12.5" rel="nofollow noreferrer">MN121:12.5</a>: There is only this that is not emptiness, namely that associated with the six sense fields dependent on this body and conditioned by life.’<br />
<a href="https://suttacentral.net/mn121/en/sujato#mn121:12.6" rel="nofollow noreferrer">MN121:12.6</a>: And so they regard it as empty of what is not there, but as to what remains they understand that it is present.<br />
<a href="https://suttacentral.net/mn121/en/sujato#mn121:12.7" rel="nofollow noreferrer">MN121:12.7</a>: That’s how emptiness is born in them—genuine, undistorted, and pure.</p>
</blockquote>
<p>That is a summary of how emptiness is understood per <a href="https://suttacentral.net/mn121" rel="nofollow noreferrer">MN121</a>. Everything else is simply stressful commentary.</p>
 471: <p>This is well explained by <a href="https://en.wikipedia.org/wiki/%E1%B9%ACh%C4%81nissaro_Bhikkhu" rel="nofollow noreferrer">Ven. Thanissaro</a> in his commentary to <a href="https://www.accesstoinsight.org/tipitaka/mn/mn.122.than.html" rel="nofollow noreferrer">MN 122</a>:</p>
<blockquote>
<p>This sutta gives many valuable lessons on practical issues surrounding
the attempt to develop an internal meditative dwelling of emptiness,
to maintain it, and to see it through to Awakening. Some of these
issues include the need for seclusion as a conducive setting for the
practice, types of conversation and thinking that are beneficial and
harmful for the practice, the dangers of being distracted by visitors,
and the proper attitude to have toward one's teacher. However, for an
explanation of emptiness in and of itself, it's necessary to look
elsewhere in the Canon.</p>
<p>There you find <strong>emptiness approached from three perspectives, treating
it (1) as a meditative dwelling, (2) as an attribute of objects, and
(3) as a type of awareness-release.</strong> The first approach is obviously
the most immediately relevant to the discussion in this sutta, but in
fact all three approaches play a role here.</p>
<p><strong>Emptiness as a meditative dwelling</strong> is most fully discussed in <a href="https://www.accesstoinsight.org/tipitaka/mn/mn.121.than.html" rel="nofollow noreferrer">MN 121</a>.
Essentially, it boils down to the <strong>ability to center the mind in a
particular mode of perception, to maintain it there, and then to
notice the absence and presence of disturbance within that mode.</strong> The
process starts with perceptions of one's external surroundings —
village, wilderness, the earth property — and then moves internally to
the four formless states, the &quot;themeless concentration of awareness,&quot;
and finally to release from all mental fermentation. Each step is
compared to the one preceding it to see how its more refined
perception engenders less disturbance. For instance, if you move from
a perception of the wilderness to a perception of earth, the first
step is to settle and &quot;indulge&quot; in that perception. Then you notice
what types of disturbance have been abandoned in the move from the
perception of wilderness to the perception of earth — for example, all
thought of the dangers of wilderness are gone — and then to see what
disturbances remain based on the latter perception. Then you abandon
the perception causing those disturbances and move on to a more
refined level of perception. This process is pursued until it arrives
at the &quot;themeless concentration of awareness.&quot; When noting that even
this refined level of concentration is fabricated, inconstant, and
subject to cessation, one gains total release from all mental
fermentations and the disturbances that would arise based on them.
This is the level of emptiness that is &quot;superior and unsurpassed,&quot; and
is apparently what the Buddha is referring to in this sutta when he
says that by &quot;not attending to any themes, he enters &amp; remains in
internal emptiness.&quot;</p>
<p>Notice that in every step along the way of this process, the emptiness
is the lack of disturbance experienced in a particular mind state.
This means that the mind state is to be perceived simply as an example
of the presence and absence of stress. In other words, emptiness in
this sense relates directly to the second of the three characteristics
— stress or suffering. The pursuit of this emptiness relates to the
four noble truths, as it looks for the causes of stress and uses
tranquility together with insight to abandon those causes in a quest
to put a total end to suffering.</p>
<p><strong>Emptiness in its second meaning, as an attribute of objects</strong>, is most
fully discussed in <a href="https://www.accesstoinsight.org/tipitaka/sn/sn35/sn35.085.than.html" rel="nofollow noreferrer">SN 35.85</a>. That sutta describes <strong>emptiness as meaning
the lack of self or anything pertaining to a self in the internal and
external sense media.</strong> Whatever sense of self that may surround these
objects is not inherent in them, and is instead simply the result of
one's own penchant for &quot;I-making&quot; and &quot;my-making.&quot; Seeing the
artificiality of &quot;I-making&quot; and &quot;my-making&quot; in this way helps lead to
a sense of disenchantment with these &quot;makings,&quot; thus helping to
abandon any clinging associated with them.</p>
<p>Thus emptiness in this sense relates directly to the third of the
three characteristics: not-self. However, just as the three
characteristics are not radically separate from one another —
everything stressful is for that reason not-self — the practical
application of this sense of emptiness is not radically different from
the first. As <a href="https://www.accesstoinsight.org/tipitaka/sn/sn12/sn12.015.than.html" rel="nofollow noreferrer">SN 12.15</a> points out, when one no longer latches onto any
idea of &quot;my self,&quot; one sees phenomena within and without simply as
examples of stress arising and passing away. To practice meditation
from this perspective — seeing each state of concentration as an
example of stress arising and passing away — is to develop emptiness
as a meditative dwelling.</p>
<p><strong>Emptiness in its third meaning, as a type of awareness-release, is an
application of emptiness in its second.</strong> <a href="https://www.accesstoinsight.org/tipitaka/mn/mn.043.than.html" rel="nofollow noreferrer">MN 43</a> describes this state of
concentration as follows: &quot;There is the case where a monk — having
gone into the wilderness, to the root of a tree, or into an empty
dwelling — considers this: 'This is empty of self or of anything
pertaining to self.'&quot; It adds that this awareness-release is different
from the awareness-release that results when one doesn't attend to any
themes. Thus this state of concentration cannot be entirely equated
with the emptiness as a meditative dwelling mentioned in this sutta.
<a href="https://www.accesstoinsight.org/tipitaka/mn/mn.106.than.html" rel="nofollow noreferrer">MN 106</a> further adds that if one frequently abides in the emptiness
awareness-release, one may either attain the dimension of nothingness
— one of the formless states — or be committed to the discernment that
will lead to Awakening. The first of these two alternatives is another
way in which emptiness as an awareness-release differs from emptiness
as a meditative dwelling as defined in <a href="https://www.accesstoinsight.org/tipitaka/mn/mn.121.than.html" rel="nofollow noreferrer">MN 121</a>. However, because the
standard definition of discernment is seeing phenomena in terms of the
four noble truths, the second alternative — being committed to
discernment — would apparently follow the same pattern suggested by <a href="https://www.accesstoinsight.org/tipitaka/sn/sn12/sn12.015.than.html" rel="nofollow noreferrer">SN
12.15</a>, above. In other words, as one no longer perceives phenomena in terms of self, one tends to view them simply as examples of stress
arising and passing away. So, again, this third meaning of emptiness,
like the second, eventually leads in practice back to the first. As <a href="https://www.accesstoinsight.org/tipitaka/mn/mn.043.than.html" rel="nofollow noreferrer">MN
43</a> notes, when one attains full awakening, the themeless
awareness-release and the emptiness awareness-release come to differ
only in name, and not in actuality.</p>
<p>In reading the following sutta, you will notice that the various
meanings of emptiness will fit some contexts better than others.
Still, it is important to remember that in the course of practice, all
three meanings are related and all will inevitably play a role in
Awakening.</p>
</blockquote>
