Crossword Genius

Donkey is on time to help (6)

Ross

I believe the answer is:

assist

'to help' is the definition.
(to assist someone is to help them)

'donkey is on time' is the wordplay.
'donkey' becomes 'ass' (ass is a term for a donkey).
'on' is a charade indicator (letters next to each other).
'time' becomes 't' (abbreviation).
'ass'+'is'+'t'='ASSIST'

(Other definitions for assist that I've seen before include "Work with N help" , "Work as a subordinate" , "Aid, abet" , "Understand by instinct" , "Help member" .)

I've seen this clue in The Sun.
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