At all

I think it could be either:

Which length description are you looking for?:

4,1,6

ever

'at all' is the definition.
(I've seen this in another clue)

This is all the clue.

(Other definitions for ever that I've seen before include "On any occasion" , "Continuously" , "In perpetuity" , "To the end of time" , "Continually" .)

I've seen this clue in The New York Times.

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