Heather's clothing remains striking (7)

I believe the answer is:

lashing

'striking' is the definition.
(lashing is a kind of striking)

'heather's clothing remains' is the wordplay.
'heather' becomes 'ling' ('ling' can be a synonym of 'heather').
'clothing' means one lot of letters goes inside another.
'remains' becomes 'ash' (I've seen this before).
'ling' enclosing 'ash' is 'LASHING'.

(Another definition for lashing that I've seen is " punishment by cat?".)

I've seen this clue in The Telegraph.

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