Liked and gave the go-ahead (8)
I believe the answer is:
approved
'liked' is the definition.
The definition and answer can be both related to thinking as well as being past participle verbs.
Perhaps you can see an association between them that I don't see?
'gave the go-ahead' is the wordplay.
I cannot quite see how this works, but
'go' could be 'rove' (roving is a kind of going) and 'rove' is found in the answer.
This explanation may well be incorrect...
'and' is the link.
Can you help me to learn more?
(Other definitions for approved that I've seen before include "Okayed" , "OK'd" , "confirmed" , "Sanctioned, authorised" , "Given the OK" .)