Green spangles not regularly available (4)

I believe the answer is:

sage

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'green' is the definition.
(sage green is a kind of green)

I don't understand the rest of the clue.

(Other definitions for sage that I've seen before include "Herb; wise person" , "Herb used in cooking" , "Fragrant herb or wise man" , "___ and onion" , "Wise green herb?" .)

I've seen this clue in The Telegraph.

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