A remarkable gesture (6)

I believe the answer is:

signal

I believe this clue is a double definition.

'a remarkable' is the first definition.
(I've seen this before)

'gesture' is the second definition.
(thesaurus)

(Other definitions for signal that I've seen before include "(Railway) light" , "Gesture encoding a message" , "Communication by sign" , "Gesture to convey information" , "Non-verbal action with an encoded message" .)

I've seen this clue in the Evening Standard.

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