irradiation vs sunray

irradiation and sunray both are nouns.

Word	Noun	Adjective	Verb	Adverb
irradiation	Yes	No	No	No
sunray	Yes	No	No	No

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

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

irradiation (noun)	sunray (noun)
(medicine) the treatment of disease (especially cancer) by exposure to a radioactive substance	a ray of sunlight
the apparent enlargement of a bright object when viewed against a dark background	a ray of artificial ultraviolet light from a sunray lamp
(Pavolvian conditioning) the elicitation of a conditioned response by stimulation similar but not identical to the original stimulus	herb having a basal cluster of grey-green leaves and leafless stalks each with a solitary broad yellow flower head; desert areas Idaho to Arizona
(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