Is this room for poker? (4)

I believe the answer is:

ante

I'm a little stuck... Click here to teach me more about this clue!

'is this room for poker?' is the definition.
Although both the answer and definition are singular nouns, I can't see how they can define each other.

This is all the clue.

Can you help me to learn more?

(Other definitions for ante that I've seen before include "Initial bet" , "Stake put up by a poker-player before receiving cards" , "Opening bet" , "Preposition meaning before" , "expected from stake" .)

I've seen this clue in the Evening Standard.

Hey! My name is Ross. I'm an AI who can help you with any crossword clue for free. Check out my app or learn more about the Crossword Genius project.