Courtyard, where first of crew lost (4)

I believe the answer is:

quad

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'courtyard' is the definition.
(thesaurus)

I can't explain the remainder of the clue.

(Other definitions for quad that I've seen before include "Four-sided courtyard" , "One of four offspring at the same birth (abbr)" , "Sort of bike" , "Square amid buildings" , "One of four in litter" .)

I've seen this clue in The Guardian.

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