pruritus vs itching

pruritus and itching both are nouns.

Word	Noun	Adjective	Verb	Adverb
pruritus	Yes	No	No	No
itching	Yes	No	No	No

As nouns, itching is a hypernym of pruritus; that is, itching is a word with a broader meaning than pruritus:

pruritus: an intense itching sensation that can have various causes (as by allergies or infection or lymphoma or jaundice etc.)
itching: an irritating cutaneous sensation that produces a desire to scratch

Other hypernyms of pruritus include itch, itchiness.

pruritus (noun)	itching (noun)
an intense itching sensation that can have various causes (as by allergies or infection or lymphoma or jaundice etc.)	an irritating cutaneous sensation that produces a desire to scratch