Speed producing strong reprimand (6)
I believe the answer is:
rocket
This clue might be a double definition.
'speed' is the first definition.
(I've seen this in another clue)
'strong reprimand' is the second definition.
'rocket' can be an answer for 'reprimand' (rocket can mean to reprimand or criticise). I am not certain of the 'strong' bit.
'producing' acts as a link.
Can you help me to learn more?
(Other definitions for rocket that I've seen before include "Projectile firework" , "Go up very quickly" , "Aerial projectile" , "go fast" , "Severe reprimand" .)