Fit properly (4)

I believe the answer is:

well

I believe this is a double definition.

'fit' is the first definition.
(associated in meaning)

'properly' is the second definition.
(thesaurus)

(Other definitions for well that I've seen before include "Competently" , "Flow up" , "run" , "Sound" , "Very; deep shaft" .)

I've seen this clue in the Evening Standard, The Globe and Mail and The Irish News.

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