Start a poker hand (4)
![Ross](/clue/static/ross-mug.min.png)
I believe the answer is:
ante
'start a poker hand' 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 "expected from stake" , "Pay" , "Hoofed mammal" , "Advance stake" , "'Behind, before (4)'" .)