In physiology, psychology, or psychophysics, a<unk>  or a<unk> al point is a sensory threshold of a physiological or psychological response. It is the boundary of perception. On one side of a<unk>  (or threshold) a stimulus is perceivable, on the other side it is not.<unk> al, as an adjective, means situated at a sensory threshold, hence barely perceptible. Subliminal means below perception. The absolute threshold is the lowest amount of sensation detectable by a sense organ.
Limen
Xilloc
Af-nest
Sultiame
Wart
Hovid 
Jim 
Clinic