Identify children's game (3)
I believe the answer is:
tag
I believe this is a double definition.
'identify' is the first definition.
(I've seen this in another clue)
'children's game' is the second definition.
(playground game)
(Other definitions for tag that I've seen before include "Tab" , "Small label" , "stock quotation" , "Label - children's game" , "Earmark" .)