effulgence vs lambency

effulgence and lambency both are nouns.

Word	Noun	Adjective	Verb	Adverb
effulgence	Yes	No	No	No
lambency	Yes	No	No	No

As nouns, lambency is a hyponym of effulgence; that is, lambency is a word with a more specific, narrower meaning than effulgence:

Other hyponyms of effulgence include gleam, gleaming, glow, luster, lustre, sheen, shininess, burnish, gloss, glossiness, polish.

effulgence (noun)	lambency (noun)
the quality of being bright and sending out rays of light	an appearance of reflected light