Escape without love that's keen (4)

I believe the answer is:

avid

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

I cannot understand how the remainder of the clue works.

(Other definitions for avid that I've seen before include "Fanatical" , "Greatly desirous" , "Zealous, enthusiastic" , "passionate" , "Excessively keen" .)

I've seen this clue in The Guardian.

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