visually challenged vs purblind

visually challenged and purblind both are adjectives.

Word	Noun	Adjective	Verb	Adverb
visually challenged	No	Yes	No	No
purblind	No	Yes	No	No

As adjectives, visually challenged and purblind are synonyms defined as:

Other synonyms of visually challenged include dim-sighted, near-blind, sand-blind, visually impaired.

visually challenged (adjective)	purblind (adjective)
having greatly reduced vision	having greatly reduced vision
	lacking in insight or discernment