It extends from Castile (7)

I believe the answer is:

elastic

'it extends' is the definition.

'from castile' is the wordplay.
'from' indicates anagramming the letters (from the letters).
'castile' anagrammed gives 'ELASTIC'.

(Other definitions for elastic that I've seen before include "Tape containing flexible rubber" , "Kind of band" , "Giving" , "Fluid" , "It's lace (anag.)" .)

I've seen this clue in The Globe and Mail.

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