pit weeds
Noun - The frontal portion of armpit hair resembling weeds in the sidewalk which remain visible even when the owners arms are at his or her side and found on persons who don't groom themselves properly... truly disgusting.
Geez bro, mix in some man-scaping! You better bust out the weed whacker and trim those nasty "pit weeds" cuz face it... you ain't gettin' no play at the pool party runnin' that shit out there!