That of a horse refusing to jump? (5)
I believe the answer is:
neigh
'jump?' is the definition.
The definition and answer can be both related to natural events as well as being singular nouns.
Perhaps you can see a link between them that I don't see?
I don't understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for neigh that I've seen before include "Whinnying sound" , "beastly noise" , "Cry coming from mount" , "Animal noise (expressing 3?)" , "Comment from stallion" .)