lambency vs effulgence

lambency and effulgence both are nouns.

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

As nouns, effulgence is a hypernym of lambency; that is, effulgence is a word with a broader meaning than lambency:

Other hypernyms of lambency include radiance, radiancy, refulgence, refulgency, shine.

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