A step at full tilt (5)

I believe the answer is:

apace

'at full tilt' is the definition.
(I've seen this in another clue)

'a step' is the wordplay.
'step' becomes 'pace' (pace is a kind of step).
'a'+'pace'='APACE'

(Other definitions for apace that I've seen before include "Swiftly, quickly" , "Quick" , "At a rapid rate" , "fast" , "flat out" .)

I've seen this clue in The Telegraph.

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