A condition in which a Costco shopper on a random shopping trip will purchase bulk items not needed but are blinded by the deal despite the large quantity that will not be used.
Witness: "That guy must be suffering from Costcosis. His cart has a 3-pack of 20lb tubs of mayo."
Person suffering from Costcosis: "That's a good price for a 3-pack of 20lb tubs of mayo."
(n.) a condition in which one has developed a cyst on one's taint. Eventually, it will surface and drain, usually oozing copious quantities of thick pus. Trust me, this hurts.
Phil: How's the taintular cystosis treating you, Bob?
Bob: I got that fucker drained, dude. The relief...it was better than sex! And what came out of it...looked like a half cup of mashed potatos!
Relating to the term "osmosis" when molecules pass through one cell to another via the call membrane, cosbmosis is the act of passing fecal matter from one person to the other through their dickhole via anal sex.
Big Easy: Yea, so, I, uh, I wouldn't recommend having anal sex if you have not already tried yet.
Tyrantula: Yea why is that?
Big Easy: While I was plugging that hole up, the nachos supreme she had earlier came right out and into my dick filling it up like it was a syringe of diarrhea.
Tyrantula: Didn't you pay attention in bioLOGy? You just went through cosbmosis.