Technically a homosexual who indulges in giving anal sex (also a heterosexual male or even female who enjoys giving anal sex). However common use of the word refers to someone, usually a friend or aqaintance, you wish to ridicule.
Billy-Bob: "Hey there goes Phinneas in his new lambo. Sweet ride huh?"

Jesus del Castro Aniston-King: "Yeh it'd be dope if he wasn't such a bumrammer."
by Simeon P Hogsnout August 30, 2006
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