The small projection of the mammary gland on the breasts (and male pectorals).
This tag should only be used when the nipples themselves are visible. If they are only noticeable through clothing by way of being erect, use covered nipples instead. The only time both can apply is when the clothing is see-through clothes.
The following tags are aliased to this tag: nipple (learn more).
The following tags implicate this tag: dark_nipples and nipple_slip (learn more).