1 n. — informal, slang, Prairies, predominantly Manitoba
a nickname for Saskatoon, Saskatchewan.
Type: 1. Origin — Saskabush appears to have been used originally as a nickname for Saskatoon, Saskatchewan. Earliest known quotations appear in University of Alberta and University of British Columbia student newspapers and may have originated among the student body there, as the term is often used in reference to rival athletic teams from the University of Saskatchewan in Saskatoon (see, e.g. the 1952 and first 1969 quotations). In fact, it is possible that the term originally designated the University of Saskatchewan, although this remains unclear. The nickname continues to be used by Saskatchewanians to refer to Saskatoon, but outside Saskatchewan is more likely to be used to refer to the entire province (see 2015 quotation) (see meaning 2).
See also COD-2, s.v. "Saskabush", which is defined as "a nickname for Saskatoon".
See also: Edmonchuk
2 n. — informal, slang, Prairies, predominantly Manitoba
a nickname for Saskatchewan.
Type: 1. Origin — Over the years, the nickname was semantically generalized to refer to the entire province of Saskatchewan and this meaning has become relatively widespread. This semantic generalization appears to have occurred outside the province, as inside Saskatchewan speakers most often use the term in reference to Saskatoon (see meaning 1). Saskabush is most prevalent in Canada (see Chart 1), and especially in the Prairies (see Chart 2).
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Chart 1: Internet Domain Search, 22 Jul. 2013 
Chart 2: Regional Domain Search, 22 Jul. 2013