Condition that makes one restless? (8)
I believe the answer is:
insomnia
'condition that makes one restless?' is the definition.
The definition and answer can be both states of affairs as well as being singular nouns.
Perhaps they are linked in a way I don't understand?
This is the entire clue.
Can you help me to learn more?
(Other definitions for insomnia that I've seen before include "Wakefulness" , "Not getting off" , "In restless state" , "Inability to drop off" , "problem at night" .)