Simple past tense and past participle of yak.(verb)
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Use "yakked" in a sentence
"He was never mean, never responded in kind when called names, never ridiculed those who disagreed with him as "the tin-foil-hat crowd," as one liberal "commentator" yakked on cable this week."
"People yakked on their cell phones as they searched through the rubble; one woman spoke in Russian over her receiver and I stared at her until she moved away."
"We yakked for a little while longer until one of the nurses shooed me out of the room."