To keep sexual intercourse to its most basic terms the peniser is the "enterer" in the coital relationship. Can be used to describe a man in heterosexual sex, "the man" in homosexual buggery and the dildo weilding lesbian. All are covered by this term. The receptical of the peniser is is it's antonym the penisee.
Damn it Margaret, I'm the breanwinner and by extension the peniser in this relationship!
(Noun) someone who does annoying things to people with his penis quite often.
"Will's such a peniser. He came all over mike's pants."