Prime clientele vendor keeps hold of (6)

I believe the answer is:

eleven

'prime' is the definition.
(eleven is a prime number)

'clientele vendor keeps hold of' is the wordplay.
'hold of' indicates the answer is hidden within the clue (I've seen 'holds' mean this).
'ELEVEN' is hidden in the letters of 'clientele vendor keeps'.

(Other definitions for eleven that I've seen before include "Smallest positive three-syllable integer" , "Sporting side" , "Cricketing side" , "Bingo's "legs"?" , "Football side" .)

I've seen this clue in The Times.

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