/ Dictionary / Index S Sioux Falls: Meaning and Definition of Find definitions for: Sioux' Falls' Pronunciation: [key] a city in SE South Dakota. 81,343. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. Sioux City Sioux State Related Content Daily Word Quiz: serendipity Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language