tenosynovitis vs tendonous synovitis

tenosynovitis and tendonous synovitis both are nouns.

Word	Noun	Adjective	Verb	Adverb
tenosynovitis	Yes	No	No	No
tendonous synovitis	Yes	No	No	No

As nouns, tenosynovitis and tendonous synovitis are synonyms defined as:

tenosynovitis and tendonous synovitis: inflammation of a tendon and its enveloping sheath

Other synonyms of tenosynovitis include tendosynovitis.

tenosynovitis (noun)	tendonous synovitis (noun)
inflammation of a tendon and its enveloping sheath	inflammation of a tendon and its enveloping sheath