Provoke cuckoo teasing it (9)
I believe the answer is:
instigate
'provoke' is the definition.
(instigate can mean to provoke or trigger)
'cuckoo teasing it' is the wordplay.
'cuckoo' is an anagram indicator (I've seen this in other clues).
'teasing'+'it'='teasingit'
'teasingit' anagrammed gives 'INSTIGATE'.
(Other definitions for instigate that I've seen before include "Prompt" , "Bring about by incitement - its eating (anag)" , "Start" , "Urge and bring about" , "Incite - set in motion" .)