Yahoo! vs Yahoo

Yahoo! and Yahoo both are nouns.

Word	Noun	Adjective	Verb	Adverb
Yahoo!	Yes	No	No	No
Yahoo	Yes	No	No	No

As nouns, Yahoo! and Yahoo are synonyms defined as:

Yahoo! and Yahoo: a widely used search engine for the web that finds information, news, images, products, finance

Yahoo! (noun)	Yahoo (noun)
a widely used search engine for the web that finds information, news, images, products, finance	a widely used search engine for the web that finds information, news, images, products, finance
	one of a race of brutes resembling men but subject to the Houyhnhnms in a novel by Jonathan Swift