tumor virus vs WTV

tumor virus and WTV both are nouns.

Word	Noun	Adjective	Verb	Adverb
tumor virus	Yes	No	No	No
WTV	Yes	No	No	No

As nouns, WTV is a hyponym of tumor virus; that is, WTV is a word with a more specific, narrower meaning than tumor virus:

tumor virus: a cell-free filtrate held to be a virus responsible for a specific neoplasm
WTV: a tumor virus transmitted by leafhoppers

Other hyponyms of tumor virus include wound tumor virus.

tumor virus (noun)	WTV (noun)
a cell-free filtrate held to be a virus responsible for a specific neoplasm	a tumor virus transmitted by leafhoppers