Speed past (4)
I believe the answer is:
sped
'speed past' is the definition.
The answer and definition are not the same part of speech. However, past participle verbs and adjectives sometimes mean the same thing.
This is the entire clue.
Can you help me to learn more?
(Other definitions for sped that I've seen before include "Rushed" , "Moved quickly" , "Went quickly" , "Hastened" , "Travelled quickly" .)