fish dumpster Share definition Flag Having sex with a dirty female hobo in a dumpster. Her vagina should smell ripe of fish. guy 1: 'You know that back alley on 5th street? I totally did a fish dumpster with some hobo chick there.'guy 2: 'Dude. That's gross.' fish dumpster by hobo_fisherman August 20, 2009 Get the fish dumpster mug.