Merges (5)
'merges' is the definition.
('fuse' can be a synonym of 'merge')
This is all the clue.
(Other definitions for fuses that I've seen before include "Electrical safety devices" , "Blends together as with heat" , "bonds" , "Blow one of these and lose your temper" , "Circuit breakers" .)
'merges' is the definition.
(I know this)
This is the entire clue.
(Other definitions for combines that I've seen before include "'Joins together, unites (8)'" , "blends" , "Joins or merges to form a single unit" , "Put together" , "Joins or puts together" .)