Misses reportedly loose (5)
I believe the answer is:
lacks
'misses' is the definition.
(lacking is a kind of missing)
'reportedly loose' is the wordplay.
'reportedly' indicates a 'sounds like' (homophone) clue.
'loose' becomes 'lax' ('lax' is associated in meaning with 'loose').
'lax' is a homophone of 'LACKS'.
(Other definitions for lacks that I've seen before include "Wants, is deficient in" , "Doesn't have" , "Has a want" , "Needs" , "Is without, wants" .)