Small amount to take in singular game (5)
I believe the answer is:
whist
'game' is the definition.
(whist is a card game)
'small amount to take in singular' is the wordplay.
'small amount' becomes 'whit' (a very small part or amount).
'to take in' indicates putting letters inside.
'singular' becomes 's' (abbreviation sometimes used in dictionaries).
'whit' going around 's' is 'WHIST'.
(Other definitions for whist that I've seen before include "Card game for four" , "Popular card game, sometimes solo" , "Trick-taking card game" , "Tricky card game" , "18th-century card game, the forerunner of bridge" .)