Double potassium

A somewhat nerdy colloquialism for "okay." As potassium's atomic symbol is K, double potassium implies "KK" which is in itself a colloquial version of "okay."

Person 1: Hey, want to meet me at Starbucks around noon?
Person 2: Sure, that sounds good.
Person 1: Great! Oh, remember to bring your notes.
Person 2: Double potassium.

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