Under way a short distance (5)

I believe the answer is:

afoot

'under way' is the definition.
(I've seen this before)

'a short distance' is the wordplay.
'short distance' becomes 'foot' (short unit of distance).
'a'+'foot'='AFOOT'

(Other definitions for afoot that I've seen before include "In the pipeline" , "Progressing, in operation - like Sherlock Holmes's game" , "About to happen" , "Going on" , "in the air" .)

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

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