Crossword Genius

Pet butterfly, say (6)

Ross

I believe the answer is:

stroke

This clue is a double definition.

'pet' is the first definition.
(thesaurus)

'butterfly say' is the second definition.
(butterfly is a kind of stroke)

(Other definitions for stroke that I've seen before include "Rower's attack?" , "Caress; pencil mark" , "Apoplexy or blow as of whip" , "It's caused by interruption in blood-flow to the brain" , "Line made by pen" .)

I've seen this clue in The Telegraph.
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