She's less than average (4)

I believe the answer is:

vera

I'm a little stuck... Click here to teach me more about this clue!

'she's' is the definition.
(I've seen this before)

'less than average' is the wordplay.
'VERA' is hidden in amongst the letters.
But, I'm uncertain how this is indicated.

Can you help me to learn more?

(Other definitions for vera that I've seen before include "__ Lynn, the forces' sweetheart" , "Duckworth, Lynn" , "Woman's name" , "and 15: Singing Dame" , "A girl to rave about" .)

I've seen this clue in the Evening Standard.

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