Want someone to contain insects (4)
I believe the answer is:
ants
'insects' is the definition.
(ant is a kind of insect)
'want someone to contain' is the wordplay.
'to contain' indicates the answer is hidden within the clue (words from the clue contain the answer).
'ANTS' is hidden in the letters of 'want someone'.
(Other definitions for ants that I've seen before include "Six-foot insects" , "Termites" , "workers found returning" , "Emmets" , "24 [INSECT] s" .)