Simple past tense and past participle of trepan. (verb)
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Use "trepanned" in a sentence
"Things like sketches by John Wayne Gacy, a trepanned skull, and even a snuff film."
"How much was intended to be religious or therapeutic? we know that these patients lived for many years after being trepanned."
"There she was, all pink and pherump and pretty, selecting a grape, dusting it with sherbert, and popping it into my mouth with a fond smirk and a loving kiss that was like being hit in the face by a handful of liver-and not two minutes earlier she'd had a dinner guest trepanned before he'd even had his coffee."