Outstanding indicator (6)

I believe the answer is:

signal

I believe this clue is a double definition.

'outstanding' is the first definition.
(thesaurus)

'indicator' is the second definition.
(thesaurus)

(Other definitions for signal that I've seen before include "Gesture, light or sound which sends a message" , "Nonverbal action or gesture that encodes a message" , "Gesture encoding a message" , "Non-verbal communication" , "Important; cue" .)

I've seen this clue in The Telegraph.

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