n. — originally informal, now common core
a Royal Canadian Mounted Police officer.
Type: 1. Origin — Mountie is a short form clipped from Royal Canadian Mounted Police officer. The North West Mounted Police (founded in 1873) and the Royal North-west Mounted Police (1904) preceded the RCMP (1920). The first quotation here (dating between 1873 and 1883) is from a poem by a member of the NWMP, Francis Henry Galt Carruthers (1853-1883). Carruthers was an early recruit; his regimental number indicates he was the 282nd Mountie appointed to the service.
Carruthers' quotation portrays Mounties as "always getting their man." The depiction of a strong, but gentlemanly, rather than "hard-boiled" hero, was a typical portrayal at the time. Dawson (1998: 35) notes "[b]etween 1890 and 1940, authors produced well over one hundred and fifty Mountie novels", and "representations of the Mountie in these books varied so little [that] readers in Vancouver, B.C., Hamilton, Ont., or Lower Sackville, N.S. all shared roughly the same image of the Mountie", which created a culturally significant trope for the entire country. This image also prevailed in movies around the same period, and later in television shows and comics. The Mountie has since become a universally recognized national symbol of Canada (see Image 1).
See Gage-1, s.v. "Mountie", which labels the term "Cdn. Informal", COD-2 & ITP Nelson, s.v. "Mountie", which mark it as "informal" but not as Canadian.
See also: Mounted Policeman musical ride barrack whisky fort
- The label informal, found in previous dictionaries, is no longer substantiated, as the term is used in all but the most traditional and formal settings. In all but the most formal settings would be the appropriate label today.
Images:

Image 1: Mounties at a parade. Source: Wikimedia Commons. Photo: A. Webber