You know that sweatstain that ladies get under their boobs? The sweat pours down the central boob canal, and out the sides in the underboob regions - thus forming the sweatstain in the shape of a mustache... aka, the Boobstache.
"yo, check out the handlebar boobstache on the girl on the elliptical."
"eh, I'm looking at the porn boobstache on the girl twerking out on the treadmill!"
slang another name for the word boobs or breasts. First used on Reddit.
"When I was around 11 or 12 my brother-in-law, who is a physician, gave me the "random fact" that the medical term for breasts is actually BOOBACLES, thus making "boob" the slang term." -ghost-from-tomorrow, Reddit.