What the cat does in the race? (4)
I believe the answer is:
laps
'does in the race?' is the definition.
The definition and answer can be both to do with fundamental existence as well as being verbs in their -s form.
Maybe you can see an association between them that I can't see?
I can't explain the rest of the clue.
Can you help me to learn more?
(Other definitions for laps that I've seen before include "Drinks; circuits" , "Circuits of track" , "Scoops up with the tongue" , "Circuits of a racetrack" , "Pals doing rounds of the track" .)