Very pale blue or green flower (4)

I believe the answer is:

nile

I believe this is a double definition.

'very pale blue or green' is the first definition.
(nile-blue and nile-green are pale colours)

'flower' is the second definition.
(Nile River is an example)

(Other definitions for nile that I've seen before include "River at Luxor" , "River associated with Cleopatra" , "River (which is originally blue and white)" , "World's longest river" , "Current" .)

I've seen this clue in The Guardian.

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