To suck your own or another's cum out of a persons ass, then spit it into their mouth. Like a mother bird feeding her young.
Johnny begged Jacob to give him a San Francisco bird feeder last night.
by J. Francis June 05, 2010
A homosexual man laying naked and face down on a park bench and waiting for homeless men to have anal intercourse with him.
I was in the park the other day and I saw a guy doing the San Francisco Bird Feeder!
by toshwatcher September 28, 2011