1) head to
head; in a competitive sense, generally reserved for
male participants.
2) cockhead to cockhead; in a sexual, possibly competitive sense, reserved for males and shemales, but could be anyone with
access to a cock or dildo.
1) "Hey man, I'm a little nervous, I've gotta
go cock to cock with Dave later at the foosball tournament, wish me
luck.."
2) "Hey man, get your cock over here and we'll go cock to cock
like we were talking about earlier.