Long narrow flag (7)

I think it could be either:

Which length description are you looking for?:

streamer

'long narrow flag' is the definition.
(I've seen this before)

This is all the clue.

(Other definitions for streamer that I've seen before include "Bit of bunting" , "Long flag -- bad cold" , "Pennant" , "Paper ribbon - thin flag" , "Long 23 ac or ribbon" .)

I've seen this clue in The Telegraph, The Times and The Guardian.

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