Assuming label covers family (6)
I believe the answer is:
taking
'assuming' is the definition.
('take' can be a synonym of 'assume')
'label covers family' is the wordplay.
'label' becomes 'tag' (synonyms).
'covers' indicates putting letters inside.
'family' becomes 'kin' (synonyms).
'tag' placed around 'kin' is 'TAKING'.
(Other definitions for taking that I've seen before include "Accepting" , "Seizing, appropriating" , "Attractive" , "Extra item added to book" , "Harm, damage" .)