Used to describe someone that's acting immature, dumb, clueless, dependent etc.
Man, you know damn well what's going on. Don't act like a fetus.
Why are you acting brand new? Or why are you acting like a fetus.
You think i was born yesterday? Or you think I'm a fetus?
Someone does something dumb** "You're such a fetus, grow up".
Holler at Cidny n see if she's around tonight. Me and Cindy chillin bring Jameson. (Whiskey)