WordNet sense 1 (a man who is virile and sexually active):

he-man, macho-man

WordNet sense 2 (ornament consisting of a circular rounded protuberance (as on a vault or shield or belt)):

rivet

WordNet sense 3 (an upright in house framing):

scantling

WordNet sense 4 (scatter or intersperse like dots or studs):

dot, constellate

WordNet sense 5 (adult male horse kept for breeding):

studhorse

WordNet sense 6 (poker in which each player receives hole cards and the remainder are dealt face up; bets are placed after each card is dealt):

stud poker