He was touchy where gold was concerned (5)
I believe the answer is:
midas
'he was touchy where gold was concerned' is the definition.
The definition suggests a singular noun which matches the answer.
This is the entire clue.
Can you help me to learn more?
(Other definitions for midas that I've seen before include "Legendary king with golden touch" , "Greek mythological king with money-making touch" , "Legendary king whose touch turned things to gold" , "Phrygian king" , "Legendary king who could turn everything to gold" .)