Simple past tense and past participle of rappel.(verb)
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Use "rappelled" in a sentence
"To avoid the steps completely, I "rappelled" down a post from the upstairs using a lamp cord."
"Subduing the beast required the combined efforts of a police sniper, who rappelled down the side of the building and fired tranquilizer darts through an open window -- this was received quite poorly by the tiger, who all but leapt out the window at the shaken officer -- and of three Bronx Zoo employees, who entered the apartment with police a while later to ensure that the tiger was, in fact, fully sedated."
"David Gray/Reuters WASHING WINDOWS: Cleaners rappelled down the front of a newly constructed building in central Beijing Tuesday."