By saying this you are mocking someone who is taking a long time to pronounce a word preceding with the letter 'T' and is stuck on the first syllable of that word.

Made famous in the film, Billy Madison
Timmy: Well, yesterda-day I decided to go to my dad's house and I t-t-t-t-t-..

John: T-T-T-TODAY JUNIOR!!!
by jayjayg7 January 11, 2012
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