One at wheel sees rock looming in wet (8)
I believe the answer is:
motorist
'one at wheel' is the definition.
Although both the answer and definition are singular nouns, I cannot see how one could define the other.
'rock looming in wet' is the wordplay.
I cannot really understand how this works, but
'rock' could be 'tor' (a tor is a rocky peak) and 'tor' is found within the answer.
'wet' could be 'moist' (similar in meaning) and 'moist' is present in the remaining letters.
No letters remain.
This may be the basis of the clue (or it may be nonsense).
'sees' acts as a link.
Can you help me to learn more?
(Other definitions for motorist that I've seen before include "One relying on car" , "Car-driver" , "One on the road" , "Traveller" , "Car driver" .)