Simple past tense and past participle of spelunk.(verb)
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Use "spelunked" in a sentence
"This bizarre yet inescapable fact has been revealed over the past 30 years, as scientists have spelunked their way through the human genome and encountered stretches of DNA with the telltale chemical signatures of viruses."
"Or did his Mummy and Daddy not show him enough affection, and his Daddy beat him for being a pansy, while his Uncle secretly spelunked his pooper in the basement?"
"For more than three decades, the Australian renaissance man has spelunked into the darkest reaches of the human soul, and he's still at it with Grinderman, whose second album growls, moans and enchants with typical Cave aplomb."