Scavenger has briefly to contain hunger (5)
I believe the answer is:
hyena
'scavenger' is the definition.
(I've seen this before)
'has briefly to contain hunger' is the wordplay.
'briefly' means to remove the last letter.
'to contain' indicates putting letters inside.
'hunger' becomes 'yen'.
'has' with its final letter removed is 'ha'.
'ha' enclosing 'yen' is 'HYENA'.
(Other definitions for hyena that I've seen before include "Dog-like scavenger" , "One laughs loud" , "Dog-like animal with laughter-like howl" , "Dog-like carrion-feeding mammal" , "He's sometimes spotted" .)