1. A male
born with a mental and physical condition that disables him from being "a good catch."
2. The guy who wont call you back. (Commonly used with a preceding derogatory adjective).
That guy has a Raiders license plate... he's probably a junkfish!
"Let's go to The Dante and have a drink or 30!" - Bottom feeder
"Alright! That place is full of junkfish!"- Bottom feeder