See the tot is playing a game (5)
I believe the answer is:
lotto
'a game' is the definition.
(lotto is a kind of game)
'see the tot is playing' is the wordplay.
'see' becomes 'lo' (archaic word meaning 'look!').
'is playing' indicates anagramming the letters.
'tot' is an anagram of 'tto'.
'lo'+'tto'='LOTTO'
(Other definitions for lotto that I've seen before include "Prize draw" , "Children's game similar to bingo" , "Children's game, housey-housey" , "Bingo-like game" , "Lucky draw" .)