actinic radiation vs actinic ray

actinic radiation and actinic ray both are nouns.

Word	Noun	Adjective	Verb	Adverb
actinic radiation	Yes	No	No	No
actinic ray	Yes	No	No	No

As nouns, actinic radiation and actinic ray are synonyms defined as:

actinic radiation and actinic ray: electromagnetic radiation that can produce photochemical reactions

actinic radiation (noun)	actinic ray (noun)
electromagnetic radiation that can produce photochemical reactions	electromagnetic radiation that can produce photochemical reactions