irradiation vs moon ray

irradiation and moon ray both are nouns.

Word	Noun	Adjective	Verb	Adverb
irradiation	Yes	No	No	No
moon ray	Yes	No	No	No

As nouns, moon ray is a hyponym of irradiation; that is, moon ray is a word with a more specific, narrower meaning than irradiation:

Other hyponyms of irradiation include heat ray, high beam, moon-ray, moonbeam, sunbeam, sunray, laser beam, low beam.

irradiation (noun)	moon ray (noun)
(medicine) the treatment of disease (especially cancer) by exposure to a radioactive substance	a ray of moonlight
the apparent enlargement of a bright object when viewed against a dark background
(Pavolvian conditioning) the elicitation of a conditioned response by stimulation similar but not identical to the original stimulus
(physiology) the spread of sensory neural impulses in the cortex
a column of light (as from a beacon)
the condition of being exposed to radiation