A worker having eaten roll, departs full (8)
I believe the answer is:
'full' is the definition.
(I've seen this before)
'a worker having eaten roll departs' is the wordplay.
'worker' becomes 'ant' (worker is a type of ant).
'having eaten' indicates putting letters inside.
'roll' becomes 'bun' ('bun' can be a synonym of 'roll'**).
'departs' becomes 'd' (common abbreviation e.g. train timetables).
'aant' placed around 'bund' is 'ABUNDANT'.
(Other definitions for abundant that I've seen before include "Luxuriant" , "Present in great quantity" , "Bountiful" , "Exuberant" , "full" .)