Show turn of speed that’s respectable (5)
I believe the answer is:
legit
This clue might be a double definition.
'show turn of speed' is the first definition.
The definition suggests a singular noun which matches the answer.
'respectable' is the second definition.
Both the answer and definition are adjectives.
Perhaps you can see an association between them that I can't see?
'that's' acts as a link.
Can you help me to learn more?
(Other definitions for legit that I've seen before include "true, in a word?" , "on the level" , "Reliable" , "Honest (abbr)" , "allowed by law, shortly!" .)