Adult's complaint reportedly raised (5-2)
I believe the answer is:
grown-up
'adult's' is the definition.
(grown-up is a kind of adult)
'complaint reportedly raised' is the wordplay.
'complaint' becomes 'groan' (I've seen this before).
'reportedly' indicates a 'sounds like' (homophone) clue.
'raised' becomes 'up' ('up' can be similar in meaning to 'raised').
'groan' sounds like 'grown'.
'grown'+'up'='GROWN-UP'
(Other definitions for grown-up that I've seen before include "Mature" , "Fully developed person" , "Matured" , "Adult" , "Big" .)