- Any of various malignant neoplasms characterized by the proliferation of anaplastic cells that tend to invade surrounding tissue and metastasize to new body sites.

- The pathological condition characterized by such growths.
A pernicious, spreading evil.

- A term often used as an insult when referring to someone who is a pathelogical source of trouble and discord within a group. Sadly, this word is usually used as an insult when the moron looking to talk trash about another person, and just can't come up with anything more original. See skippy mcnipplehead, hag, clannie, chickenshit, and the queen.
Use one and two: "How sad, did you hear about George? He was diagnosed with cancer."

Use three: "I'm taking measures to make sure that this crap doesn't happen anymore. I usually try to stay out of it, but I've hit my limit. Now it's my turn. Remove the cancer...then and only then can the healing begin. We'll be ok."

To which a proper response would be...

"Hell, If we're "CANCER", then ya'll are "AIDS", because at least we only destroy ourselves... you people destroy each other."
by The Cancer Coven November 22, 2004
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Something that my mom told me I have but I still don’t know what it is..
by Gonefortea March 05, 2021
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a term used to describe something bad, stupid, or all around toxic. used in a bad sense because fuck cancer.
Guy 1: you like my shirt
Guy 2: no that's cancer take it off
Guy 1: screw you guy
by mega male February 04, 2021
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Online Social Meanings, mostly used in forums:
Group of people who encourages more people (hence cancer's spreading nature) go join a certain forum with then corrupts the traditions and influenced (usually in a faggotry sense) the forum.

In other words, Newfags in numbers who couldn't shut up.
The cancer has killed this forum, lets go somewhere else.
by Anonymous asdfasdf July 25, 2008
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