Simple past tense and past participle of deadpan.(verb)
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Use "deadpanned" in a sentence
"In 2000 he organised a counter-exhibition to the Shanghai bienniale, with the blunt English title "Fuck Off", a phrase deadpanned into Chinese as "Unco-operative Approach"."
"After a brief discussion about the vintage of the decade, Christian Seely again deadpanned “I want to be clear: 2009 really is the vintage of the century.”"
"Mr. McCain deadpanned, “I was trying to hear through the wall.”"