Used when you want to say the same thing in return to someone, but you can't be arsed to type the full thing. Means 'same here' pretty much.
Dude 1: I love you

Dude 2: Ditto

Dude 1: Aww
by Dubstep Froggo August 17, 2012
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it seems nobody got the real source yet:
'Ditto' comes from Latin, and means about 'as has been said before'. So most of the other explanations are correct.
there's a lot of examples around already.
Ditto.
by Bill Bigfoot April 10, 2007
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1. Also, or the same

2. A purple/pink transform Pokemon that looks like a blob.
1. Person 1: DAMN HE'S FINE.
Person 2: DITTO!

2. Dittos are my favorite Pokemon.
by JellyDinosaur February 16, 2012
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ditto mark: a mark used to indicate the word above it should be repeated
repeat an action or statement; "The next speaker dittoed her argument".

The word "ditto" is commonly used as a way of saying "me too", or "I agree".
Person 1: "I hate you!"
Person 2: "Ditto!"

Person 3: "I love this song!"
person 3: "Ditto!"
by Malicious Matt August 22, 2005
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Worst word in the english language. It is the laziest word, it is just an excuse not to respond properly.
"I love you, hope you have a good day tomorrow"
-"ditto"
by Erica I. November 4, 2010
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A pokemon created for all other pokemon to have pleasure and sex by transforming.
Person 1: Dude I just put a ditto and a charizard and i got charmanders!
Person 2: Of course! That's why ditto is a sex machine!
by drexlerf February 8, 2011
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