“Yada yada yada” (Seinfeld)

Why bother explaining the messy part when you can just yada yada right over it? Seinfeld took an existing expression and built an entire comic premise around everything people conveniently leave unsaid. That gives this contender a different case from the character-owned phrases: it’s less about an impression and more about a phrase that fits suspiciously well into real conversation. Put it against “Bazinga!” and you get two completely different definitions of a sitcom catchphrase. Put it against “How you doin’?” and suddenly delivery matters a whole lot more. You can yada yada the details, but you still have to pick a winner.