Simple past tense and past participle of simper.(verb)
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Use "simpered" in a sentence
""Oh good sir, you make me blush at your delicious impertinence," she might have simpered, had this been a bad Jane Austen production, and not a woman just trying to do her job at Westminster."
"‘Thanks Dad’ Frank replied with a weak smile, his mother simpered quietly."
""Ah, that's a good one, boss," Official Toady Richter simpered."