night blindness vs nyctalopia

night blindness and nyctalopia both are nouns.

Word	Noun	Adjective	Verb	Adverb
night blindness	Yes	No	No	No
nyctalopia	Yes	No	No	No

As nouns, night blindness and nyctalopia are synonyms defined as:

night blindness and nyctalopia: inability to see clearly in dim light; due to a deficiency of vitamin A or to a retinal disorder

Other synonyms of night blindness include moon blindness.

night blindness (noun)	nyctalopia (noun)
inability to see clearly in dim light; due to a deficiency of vitamin A or to a retinal disorder	inability to see clearly in dim light; due to a deficiency of vitamin A or to a retinal disorder