Top part of an apron (3)
I believe the answer is:
bib
'top part of an apron' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for bib that I've seen before include "Tempest airy spirit" , "Protective cloth; fish" , "drink" , "Palindromic protective cloth for child while eating" , "Top part of an apron" .)