Vessel one fills inside? (5)
I believe the answer is:
liner
This clue could be a double definition.
'vessel' is the first definition.
(liner is a kind of vessel)
'one fills inside?' is the second definition.
Although both the answer and definition are singular nouns, I cannot understand how one could define the other.
Can you help me to learn more?
(Other definitions for liner that I've seen before include "LP's inner sleeve" , "bin-bag?" , "may be demonstrated by make-up artist" , "that's found in the kitchen bin, perhaps" , "Craft" .)