gossip vs rumor

gossip and rumor both are nouns.

Word	Noun	Adjective	Verb	Adverb
gossip	Yes	No	Yes	No
rumor	Yes	No	Yes	No

As nouns, rumor is a hyponym of gossip; that is, rumor is a word with a more specific, narrower meaning than gossip:

gossip: a report (often malicious) about the behavior of other people
rumor: gossip (usually a mixture of truth and untruth) passed around by word of mouth

As verbs, rumor is a hyponym of gossip; that is, rumor is a word with a more specific, narrower meaning than gossip:

gossip: wag one's tongue; speak about others and reveal secrets or intimacies
rumor: tell or spread rumors

Other hyponyms of gossip include bruit, rumour.

gossip (noun)	rumor (noun)
light informal conversation for social occasions	gossip (usually a mixture of truth and untruth) passed around by word of mouth
a report (often malicious) about the behavior of other people
a person given to gossiping and divulging personal information about others

gossip (verb)	rumor (verb)
wag one's tongue; speak about others and reveal secrets or intimacies	tell or spread rumors
talk socially without exchanging too much information