Endorse token gesture (11)
I believe the answer is:
countersign
'endorse' is the definition.
(thesaurus)
'token gesture' is the wordplay.
'token' becomes 'counter' (I've seen this in other clues).
'gesture' becomes 'sign' (sign is a kind of gesture).
'counter'+'sign'='COUNTERSIGN'
(Other definitions for countersign that I've seen before include "Authorise" , "Add a second signature" , "Attest authenticity" , "Add name" .)