Nar

A generic filler word used when you're at loss for the correct interjection, or you must refrain from cursing.

(possible substitution for a word)

Rambling: "Oh, and I'm so funny, nar nar nar nar."

Angry: "My freaking computer! NARRRRRRR"

And I think you should be creative in thinking of situations appropriate for the usage of this word.

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