'Speed', said to be high (3)

I believe the answer is:

hie

'speed' is the definition.
('hie' can be a synonym of 'speed')

'said to be high' is the wordplay.
'said to be' shows a homophone (sound like).
'high' is a homophone of 'HIE'.

(Other definitions for hie that I've seen before include "Hasten" , "Make one's way quickly" , "Go quickly (archaic)" , "Be quick (lit.)" , "make haste" .)

I've seen this clue in the Evening Standard.

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