Threaten youngster on reservation? (5,2)
I believe the answer is:
creep up
'threaten' is the definition.
Although both the answer and definition are verbs in their base form, I cannot understand how one could define the other.
'youngster on reservation?' is the wordplay.
'youngster' becomes 'pup' (I've seen this in other clues).
'on' says to put letters next to each other.
'reservation?' becomes 'cree' (I can't explain this - if you can you should give a lot more credence to this answer).
'pup' after 'cree' is 'CREEP UP'.
Can you help me to learn more?
(Another definition for creep up that I've seen is " Approach slowly and without warning".)