Osoyoos (/ɒˈsuːjuːs/ o-SOO-ews,[2] historically /ˈsuːjuːs/ SOO-ews)[4] is the southern-most town in the Okanagan Valley in British Columbia between Penticton and Omak. Near the border with Washington state, the town is also adjacent to the Indian Reserve of the Osoyoos Indian Band.[4] The origin of the name Osoyoos was the word sẁiẁs (pronounced "soo-yoos") meaning "narrowing of the waters" in the local Okanagan language (Syilx'tsn). The "O-" prefix is not indigenous in origin and was attached by settler-promoters wanting to harmonize the name with other O-names in the Okanagan Country (Oliver, Omak, Oroville, Okanogan).