The word neigh is spelt as you have in the question.
Nae pronounced like a horse neigh
Although it is sometimes spelled 'neigh', it is more commonly spelled 'nay'.
They make a small whistle like neigh
A neigh if it a loud full call that sounds like the horse is saying: neeeeeeiiiighhh!, a whinny if it a high pitched call that sounds like the horse is saying: whinnnnnny! and a nicker if it is a low repeated sound that sounds like the horse is laughing. The nicker is quieter than a whinny/neigh
I heard the horse neigh. The horse could neigh loudly at times.
Neigh!
Clippity-clop, clippity-clop, clippity-clop. or: thubalup, thubalup..
The sounds a horse makes are usually written as a "neigh" or a "whinny".
Horses At a Horse Trial: "How does the defendant plead - Guilty or Not Guilty?" "Neigh!"
a female horse
neigh.
a neigh