Describing leaves: couple mostly greenish-blue (8)

I believe the answer is:

bracteal

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'describing leaves couple mostly greenish-blue' is the definition.
I can't tell whether this defines the answer.

'couple mostly greenish-blue' is the wordplay.
'couple' becomes 'brace' (brace can mean a pair of something).
'mostly' means to remove the last letter (most but not all of the word).
'greenish-blue' becomes 'teal' (I've seen this before).
'brace' with its last letter taken away is 'brac'.
'brac'+'teal'='BRACTEAL'

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I've seen this clue in The Independent.

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