Vest feature (7)

I believe the answer is:
armhole
(Other definitions for armhole that I've seen before include "Garment opening" , "Feature of coat" , "Garment aperture" , "Space" , "part of jacket" .)
I believe the answer is:
armhole
(Other definitions for armhole that I've seen before include "Garment opening" , "Feature of coat" , "Garment aperture" , "Space" , "part of jacket" .)