spam vs e-mail

spam and e-mail both are nouns.

Word	Noun	Adjective	Verb	Adverb
spam	Yes	No	Yes	No
e-mail	Yes	No	Yes	No

As nouns, e-mail is a hypernym of spam; that is, e-mail is a word with a broader meaning than spam:

spam: unwanted e-mail (usually of a commercial nature sent out in bulk)
e-mail: (computer science) a system of world-wide electronic communication in which a computer user can compose a message at one terminal that can be regenerated at the recipient's terminal when the recipient logs in

Other hypernyms of spam include electronic mail, email.

As verbs, e-mail is a hypernym of spam; that is, e-mail is a word with a broader meaning than spam:

Other hypernyms of spam include email, netmail.

spam (noun)	e-mail (noun)
unwanted e-mail (usually of a commercial nature sent out in bulk)	(computer science) a system of world-wide electronic communication in which a computer user can compose a message at one terminal that can be regenerated at the recipient's terminal when the recipient logs in

spam (verb)	e-mail (verb)
send unwanted or junk e-mail	communicate electronically on the computer