vision defect vs disability

vision defect and disability both are nouns.

Word	Noun	Adjective	Verb	Adverb
vision defect	Yes	No	No	No
disability	Yes	No	No	No

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

vision defect: impairment of the sense of sight
disability: the condition of being unable to perform as a consequence of physical or mental unfitness

Other hypernyms of vision defect include disablement, handicap, impairment.

vision defect (noun)	disability (noun)
impairment of the sense of sight	the condition of being unable to perform as a consequence of physical or mental unfitness