I'll bequeath things with hostility (3,4)
I believe the answer is:
ill will
'hostility' is the definition.
(synonyms)
'i'll bequeath things' is the wordplay.
I cannot really see how this works, but
'i'll' could be 'ill' and 'ill' is found within the answer.
'bequeath' could be 'will' (synonyms) and 'will' is present in the answer.
No letters remain.
This explanation may well be incorrect...
'with' acts as a link.
Can you help me to learn more?
(Other definitions for ill will that I've seen before include "Bad feeling towards, hostility" , "Bitterness" , "'Hostility or dislike (3,4)'" , "causing resentment" , "Hostile and unkind feeling" .)