Given away (8)
I believe the answer is:
betrayed
'given away' is the definition.
(betraying is a kind of giving away)
This is all the clue.
(Other definitions for betrayed that I've seen before include "Was disloyal, assisted enemy" , "Was unfaithful" , "Gave away" , "Handed over or exposed a friend to an enemy" , "sold down the river" .)