Pouch (3)
'pouch' is the definition.
(I know that pouch can be written as sac)
This is all the clue.
(Other definitions for sac that I've seen before include "Traditional entitlement to hold court" , "Bag-like part in animal or plant" , "Membranous cavity" , "Bodily cavity enclosed by a membrane" , "Pouch in the body" .)
'pouch' is the definition.
(I know that pocket is a type of pouch)
This is the entire clue.
(Other definitions for pocket that I've seen before include "Take; isolated patch" , "One of six pouches on snooker table" , "A ball-catching pouch on a snooker table" , "Pot a snooker ball into the ....." , "Take for oneself" .)
(Other definitions for sachet that I've seen before include "Small bag or packet" , "Small bag with sweet-smelling substance" , "Little sealed packet" , "Small soft container -- a chest (anag)" , "Package" .)