"Dease Creek" adopted in the 1st Report of the Geographic Board of Canada, 1898. Also Dease Lake. Form of name changed to Dease River in the 3rd Report of the Geographic Board of Canada, 30 June 1901. Re-adopted 28 December 1944 on 104NE, 9 June 1948 on 104P/14, and 30 June 1950 on 104P. See Dease Lake for origin information.
Source: BC place name cards, or correspondence to/from BC's Chief Geographer or BC Geographical Names Office