(n. pl.) - When speaking in public, you experience a sudden coughing fit - but you try to talk your way through it, leading the audience to possibly hear something you didn't actually say.
Cough Derps in action:

What you said: "And so, you can see that *cough* 'is *choke* 's *hack* 'very *chork*"

What you thought you said: "And so, you can see that this rare situation occurs in every byte."

What the audience heard: "And so, you can see that his rate of masturbation is very high."
by The Real Egon Spengler October 5, 2013
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