e-mail vs spam

e-mail and spam both are nouns.

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

As nouns, spam is a hyponym of e-mail; that is, spam is a word with a more specific, narrower meaning than e-mail:

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
spam: unwanted e-mail (usually of a commercial nature sent out in bulk)

Other hyponyms of e-mail include freemail, junk e-mail.

As verbs, spam is a hyponym of e-mail; that is, spam is a word with a more specific, narrower meaning than e-mail:

e-mail (noun)	spam (noun)
(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	unwanted e-mail (usually of a commercial nature sent out in bulk)

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