Maybe it was the narrow part (5)
I believe the answer is:
waist
'the narrow part' is the definition.
(I've seen this before)
'maybe it was' is the wordplay.
'maybe' is an anagram indicator.
'it'+'was'='itwas'
'itwas' anagrammed gives 'WAIST'.
(Other definitions for waist that I've seen before include "Midriff" , "Band may go round here" , "Middle part of a ship" , "Between ribs and hips" , "Spare tyre location?" .)