I'll shed some light on how I construe these terms for calling in poker while I'm at it.

Peel - Generally a tentative call with implications that A: your hand probably isn't too strong and B: You're going to decide more stuff when the next card comes off, or you want to see the next card + how villain plays the next street. Peel comes from the next card "peeling" off, so calling is to cause the peeling of the next card.

Float - Call a bet postflop without a strong hand with the intention of winning the pot at a future point. Can be done with or without non made hand equity.

Flat - Just a standard name for calling, usually preflop. I wouldn't say it has to be with a hand you may otherwise 3-bet. I'd say "So I flat 88 on the BU vs the UTg open." I'd always flat 88 here, but don't think the use of flat is inappropriate.

Smooth Call - A live term for flatting a hand you could certainly have 3 bet. EG> "OMG Jesse, Chirs Ferguson has elected to smooth call his Cowboys!"

Here are some other ones:

CIB (click it back) - To min raise someone's bet preflop or post flop usually quickly. Seen as cheeky/tilting/inducing.

Re-pop - Horrible ugly dumb sounding live term for reraising preflop (3, 4 or 5 betting etc) or raising at some point post flop.

Stab - To bet in order to take a shot at winning a pot when noone else has bet, usually with very minimal equity or none.

There are probably loads more you'll come across too.