twilight vision vs vision

twilight vision and vision both are nouns.

Word	Noun	Adjective	Verb	Adverb
twilight vision	Yes	No	No	No
vision	Yes	No	No	No

As nouns, vision is a hypernym of twilight vision; that is, vision is a word with a broader meaning than twilight vision:

twilight vision: the ability to see in reduced illumination (as in moonlight)
vision: the ability to see; the visual faculty

Other hypernyms of twilight vision include sight, visual modality, visual sense.

twilight vision (noun)	vision (noun)
the ability to see in reduced illumination (as in moonlight)	the ability to see; the visual faculty
	the perceptual experience of seeing
	a vivid mental image
	the formation of a mental image of something that is not perceived as real and is not present to the senses
	a religious or mystical experience of a supernatural appearance