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1.
TMSIDK is the abbreviation of Tell Me Something I Don't Know. To show sarcasm at the obvious.
Person 1: "It's raining out"

Person 2: "Tell Me Something I Don't Know"

Can also look at sites like www.tmsidk.com for more info.
by agnoster August 19, 2010

Words related to Tell Me Something I Don't Know

duh tmsidk