Quite a large lake (3)

I believe the answer is:

all

'quite' is the definition.
(thesaurus)

'a large lake' is the wordplay.
'large' becomes 'l'.
'lake' becomes 'l'.
'a'+'l'+'l'='ALL'

(Other definitions for all that I've seen before include "Total" , "'... things come to those who wait'" , "Avenue, walk or garden path" , "Long avenue or garden path" , "Every single one" .)

I've seen this clue in The Telegraph and The Times.

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