First chip in the poker pot (4)
I believe the answer is:
ante
'first chip in the poker pot' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for ante that I've seen before include "Poker pot starter" , "Card-player's stake" , "Money for poker" , "Player's stake in poker - a ten? (anag)" , "not post" .)