Being unfamiliar with one's surroundings/activities thus often being vulnerable in such circumstances.
Commonly used to describe a change in surroundings by phrases such as 'going
fish out of water' or 'to
go fish out of water.'
In this sense, the meaning is similar to the term 'Slippin' meaning to leave one's usual abode/habitat to enter next manz
endz.
i.e.
Brare 1: Yo blud
come we roll down (enter
endz of choice here), still.
Brare 2: Rah!!! Allow goin' Fish out of Water down dere blud, manz gonna get merked ugetme?!
Brare 1: Oh yes, I suppose you're right old bean. Silly me.