One less brutal to a shrinking flower (6)

I believe the answer is:

violet

I'm a little stuck... Click here to teach me more about this clue!

'flower' is the definition.
(I've seen this before)

I cannot understand how the remainder of the clue works.

(Other definitions for violet that I've seen before include "It nods on Oberon's bank" , "Rainbow colour; flower" , "Bloomer" , "Colour at opposite end of spectrum from red" , "Colour; flower, source of fragrance" .)

I've seen this clue in the Sydney Morning Herald.

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