Uncle of numerous Americans (3)

I believe the answer is:

sam

'uncle' is the definition.
(Uncle Sam is an example)

'of numerous americans' is the wordplay.
'of' indicates a hidden word.
'SAM' is hidden within 'numerous americans'.

(Other definitions for sam that I've seen before include "Boy" , "together once" , "Uncle" , "Casablanca piano player" .)

I've seen this clue in the Evening Standard.

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