Tom's on a high, OK? (6,2)

I believe the answer is:

thumbs up

'ok?' is the definition.
(both can mean approval)

'tom's on a high' is the wordplay.
'tom's' becomes 'Thumb's' (folklore character Tom Thumb).
'on a high' becomes 'up'.
'thumbs'+'up'='THUMBS-UP'

(Other definitions for thumbs up that I've seen before include "Indication of approval" , "gets green light, perhaps" , "Manual sign of approval" , "Approving gesture" , "Digital signal" .)

I've seen this clue in The Guardian.

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