Examine small container (4)
I believe the answer is:
scan
'examine' is the definition.
(I know that scan is a more specific form of the action examine)
'small container' is the wordplay.
'small' becomes 's' (abbreviation - e.g. clothes size).
'container' becomes 'can' (can is a kind of container).
's'+'can'='SCAN'
(Other definitions for scan that I've seen before include "convert metres into feet?" , "Inspect" , "Look briefly through" , "Look over (in order to copy?)" , "Medical examination" .)