n. — Slang, potentially derogatory
a nickname for Calgary, Alberta.
Type: 5. Frequency — Cow-town has been used in the US since the 1880s to refer to "a town forming a local centre in a stock-raising district; a small, isolated town" (OED-3, s.v. "cow (n.3, C1: cow-town"); DAE attests the term as early as 1888, with the defintion of
'a town situated in a cattle-raising district, esp. one from which large shipments of cattle are made'. Note that DARE does not list the term, so it may not have a regional character in the US). A semantic transfer and specialization of the name to Calgary, incorporated as a town in 1884, is the preferred scenario over theories of an independent re-creation of the term, given the widespread dissemination of the basic meaning. The nickname derives from Calgary's role as a major centre of the cattle and meat packing industries.
Note that COD-2 distinguishes between Cowtown, which is Calgary, and cowtown, which is any cattle-producing centre, though this orthographic distinction is not always borne out in the data. As can be seen in Chart 1, the term is, despite other locations and places so called, most frequent in Canada, especially so in the North American context. Chart 2 shows the prevalence of the term in Quebec, known for dairy farming, and where it also appears to be a nickname for Cowansville, QC. Use of the term is also frequent in Alberta and Saskatchewan. In the national and international contexts, Calgary is by far the most widely recognized cowtown.
See also: Hogtown
- Depending on who uses the term, it may carry connotations from endearing to pejorative.
Images:

Chart 1: Internet Domain Search, 19 Apr. 2016
Chart 2: Regional Domain Search, 21 Nov. 2015