severity vs intensity

severity and intensity both are nouns.

Word	Noun	Adjective	Verb	Adverb
severity	Yes	No	No	No
intensity	Yes	No	No	No

As nouns, intensity is a hypernym of severity; that is, intensity is a word with a broader meaning than severity:

Other hypernyms of severity include intensiveness.

severity (noun)	intensity (noun)
excessive sternness	high level or degree; the property of being intense
used of the degree of something undesirable e.g. pain or weather	chromatic purity: freedom from dilution with white and hence vivid in hue
something hard to endure	the magnitude of sound (usually in a specified direction)
extreme plainness	the amount of energy transmitted (as by acoustic or electromagnetic radiation)