Far West DCHP-1 (pre-1967)
1 — Obs.
until about 1840, that part of Upper Canada now known as Western Ontario. See 1845 quote at def. 2.
2
after about 1840, the territories west of Upper Canada, progressively Manitoba, Saskatchewan, Alberta, and British Columbia, as settlement moved westward; in present-day use the term usually refers to the region west of the Prairies.