wiktionary
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Borrowed from Kansa tó ppí kʼé([dopĩkʼʔə], literally “good place to dig potatoes”)
etymonline
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Topeka
city in Kansas, U.S.A., from Kansa (Siouan), literally "a good place to dig potatoes;" from /do/ "wild potato" + /ppi/ "good" + /ke/ "to dig."
