1. Nintendo characters; A race of turtle-like reptiles that come in all shapes and sizes. Most of them are Bowser's servants, but there are also a lot of good Koopas. Bowser's Koopas have many various soldier ranks, most common of which is "Koopa Troopas" (which is another word for "troopers", if I'm not mistaken).

2. Koopa is also the name of their king. Koopa or King Koopa, also known as Bowser or Lord Bowser. But anyone who watched old Mario cartoons or played Super Smash Bros. Melee on Japanese mode knows that already.
Ahem. Anyway, his full name (as far as I know) is King Bowser Koopa.
1. "Uh oh. There's an army of Koopas approaching us."

2. "Hi, Master Koopa! Whatcha doin'?"
by M. the gamin' gangsta July 24, 2005
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To give generously. Someone who donated more than they receive.
That guy is Koopa the way he donates troops in Clash of Clans.
by Graven79 March 08, 2016
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A koopa troopa that has not yet ascended to the rank of troopa. May work in a grocery store or gas station. If it does not become a troopa within one year, it is put to death by squashing.
"That koopa is a waste of pixels. Lets go jump on his unshelled ass. Then we'll go get a pizza and do some plumbing."
by Luigi Mario March 03, 2005
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It was first commonly used while cruising around the "Beach" (a specific area) of Toronto in the summer of 2007. "Koopa" is correctly used when you drive pass an ugly person in your car and yell the word "koopa".
"Oh shit man roll down the window"...(window is rolled down)... "KOOPA! KOOPA! KOOPA!"
by reinprecht November 07, 2007
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A phrase of which the definition or explanation is commonly asked, but actually, no one knows what it means.
-What's a Koopa Cat!?!?
-No one knows....
by Webbie Frebbie November 11, 2013
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1.) The secret 8th koopaling from the Mario series. Looks like a regular koopa troopa but has a big heart.

2.) The kind of guy who always wants to be invited to parties but never shows up. Bob Koopas are usually really hot and have beautiful eyes, are also a master of the arts and have talent oozing out of their shells. When you see a guy who's really sexy, you know he's a Bob Koopa. This chelidae has it all. Just don't expect to ever see one because they never show up for anything. Loves cock.
Person 1: "Hey, did you see that hot guy over there? He's a total Bob Koopa."
Person 2: "Naw, they never showed up to the party."
by robert kooparoni July 17, 2016
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