The word caining comes from a primitive method of stealing from shops especially ones that sell clothes. The process of caining involves pushing a long bamboo cain through the letter box of the shop you are trying to rob and hooking items (IE clothes) off the rails and by tilting the cain upwards the items slide to the mouth of the letter box where they are easily pulled though. The phrase became associated with the UK drug culture in the mid 90's as caining was an easy way of obtaining money to buy drugs.
The word 'cained' refers to being off your face with the money you made from caining.As the price of drugs like Ecstasy dropped as much as 1/20th of the original street price the need for large amounts of money to buy drugs had decreased and the word is now used as a general term that refers to any state of altered consciousness gained through the use of illegal drugs.
If someone is said to be cained it usually means they have taken so much mind altering substances that they are physically incapable of taking any more.
" ...you were caining loads of pills last night dude..
by Snowy_uk_west February 11, 2006
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Someone that practises sex positions on domestic cats and other felines.
by gester11 October 4, 2011
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To use a lot of. To do something in abundance or excess.

Or, very drunk/intoxicated.
"I was caining it down the motorway"
"I'm caining The Beatles at the minute, I can't get enough of them!"

"I was cained lastnight!"
by anynymooose January 8, 2012
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'Cained' is the desired stage one should be aiming for when out smoking pot with his buddies. It's more intense then a 'high,' but has yet to go into 'stoned.'
"I'd introduce you to the parents, dude, but you're a bit cained."
by Rep August 24, 2004
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To intake large amount of illegal narcotics, traditionally marijuana. To cain means to go above and beyond normal intakes to the amount that will physically challenge you and to do it at a fast pace.
"Jordan cains like a muvaf*ck"
"Right lads facny a caining session?"
"Ben was well cained, puking up solid jelly babies....."
by Garreth Hughes May 27, 2004
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Cain can be explained plainly as finishing off a drug quantity, whether it be a cannabis cigarette, shesha bong or anything else of the sort. Caining is to devour the last remains of something OR to devour it rapidly in quick consession.
Example 1: Dude, that last pull was a real lung tickler, I'm out for the count, cain that shit.

Example 2: My Dad'll be home soon, let's cain his Jack Daniels before he gets home.

Example 3: What ho! Those chicken nuggets are getting cained! I best get out a fresh box for yowl.
by tenspeedgeek January 10, 2008
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