user125: In Vinaya, there is this rule (copied from Buddhist Monastic Code II):

"One should not knowingly consume meat killed on purpose (for a
  bhikkhu). Whoever should consume it: an offense of wrong doing. I
  allow fish and meat that is pure in three respects: One has not seen,
  heard, or suspected (that it was killed on purpose for a bhikkhu)." —
  Mv.VI.31.14

How should we interpret "heard"? I can think of some possibilities:

Heard from someone that it was killed for me, i.e., someone told me that it was killed for me.
Heard the sound of killing, e.g. sound of the animal or action of killing
Both of the above.


user533: I would say hear = hear the sound of the animal being killed/ screaming (not for fish or course)
This is based on the interpretation of Dhammavvuddho Thero, he has written a book that contains this subject and also he has given many Dhamma Talks about meat eating. You can google it maybe you will find more details.
He says you should not eat if you see the animal being killed, hear it or suspect it was killed intentionally killed for you, of course you cannot kill or ask someone to do it as well.
There's also another detail: Not all types of meats are allowed, some animals and human flesh should not be consumed for many reasons.
More details here (from Theravada monk Dhammavvuddho Thero):
http://thedailyenlightenment.com/2010/07/the-buddha’s-real-views-on-meat-eating/

user254: This translation says,

If a bhikkhu sees, hears or suspects that it has been killed for him, he may not eat it.

This commentary says,

Furthermore, even cooked fish or meat of an allowable kind is unallowable if the 
  bhikkhu sees, hears, or suspects that the animal was killed specifically for the 
  purpose of feeding bhikkhus.

Both of these imply only the first of your two possibilities.

125: <p>In Vinaya, there is this rule (copied from <a href="http://www.pratyeka.org/a2i/lib/authors/thanissaro/bmc2/bmc2.ch04.html" rel="nofollow">Buddhist Monastic Code II</a>):</p>

<blockquote>
  <p>"One should not knowingly consume meat killed on purpose (for a
  bhikkhu). Whoever should consume it: an offense of wrong doing. I
  allow fish and meat that is pure in three respects: One has not seen,
  heard, or suspected (that it was killed on purpose for a bhikkhu)." —
  Mv.VI.31.14</p>
</blockquote>

<p>How should we interpret "heard"? I can think of some possibilities:</p>

<ol>
<li>Heard from someone that it was killed for me, i.e., someone told me that it was killed for me.</li>
<li>Heard the sound of killing, e.g. sound of the animal or action of killing</li>
<li>Both of the above.</li>
</ol>
 533: <p>I would say hear = hear the sound of the animal being killed/ screaming (not for fish or course)</p>

<p>This is based on the interpretation of Dhammavvuddho Thero, he has written a book that contains this subject and also he has given many Dhamma Talks about meat eating. You can google it maybe you will find more details.</p>

<p>He says you should not eat if you see the animal being killed, hear it or suspect it was killed intentionally killed for you, of course you cannot kill or ask someone to do it as well.</p>

<p>There's also another detail: Not all types of meats are allowed, some animals and human flesh should not be consumed for many reasons.</p>

<p>More details here (from Theravada monk Dhammavvuddho Thero):</p>

<p><a href="http://thedailyenlightenment.com/2010/07/the-buddha" rel="nofollow">http://thedailyenlightenment.com/2010/07/the-buddha</a>’s-real-views-on-meat-eating/</p>
 254: <p><a href="http://www.accesstoinsight.org/lib/authors/ariyesako/layguide.html#meat" rel="nofollow">This translation</a> says,</p>

<blockquote>
  <p>If a bhikkhu sees, hears or suspects that it has been killed for him, he may not eat it.</p>
</blockquote>

<p><a href="http://www.accesstoinsight.org/lib/authors/thanissaro/bmc1.pdf" rel="nofollow">This commentary</a> says,</p>

<blockquote>
  <p>Furthermore, even cooked fish or meat of an allowable kind is unallowable if the 
  bhikkhu sees, hears, or suspects that the animal was killed specifically for the 
  purpose of feeding bhikkhus.</p>
</blockquote>

<p>Both of these imply only the first of your two possibilities.</p>
