chipmunk

The word comes from Ojibwe ačitamo˙nˀ (modern ajidamoo), meaning "squirrels," literally "those who descend headlong," built from ačit- ("headfirst, face-down"). English speakers reshaped the earlier form chitmunk into chipmunk around 1832, likely influenced by the phrase "chipping squirrel."

Beyond the 1832 spelling shift, the word later gained a verb sense in English — to "chipmunk" a voice, meaning to speed it up into a high-pitched squeak, a use inspired by the puppet and cartoon group Alvin and the Chipmunks and their 1980s TV show.

The Ojibwe root ačit- also appears in ajijibizo ("he falls headfirst") and ajidagoojin ("he hangs upside down"), both describing the same tumbling, upside-down motion.