glint vs brightness

glint and brightness both are nouns.

Word	Noun	Adjective	Verb	Adverb
glint	Yes	No	Yes	No
brightness	Yes	No	No	No

As nouns, brightness is a hypernym of glint; that is, brightness is a word with a broader meaning than glint:

glint: a spatially localized brightness
brightness: the location of a visual perception along a continuum from black to white

glint (noun)	brightness (noun)
a spatially localized brightness	the location of a visual perception along a continuum from black to white
a momentary flash of light	the quality of being luminous; emitting or reflecting light
	intelligence as manifested in being quick and witty

glint (verb)	brightness (verb)
be shiny, as if wet
throw a glance at; take a brief look at