n. — in compounds, e.g. seniors lodge
a retirement home for seniors.
Type: 3. Semantic Change — The term lodge was likely applied to seniors' homes in relation to "a residence or hotel. (Freq. as the second element of house- or hotel-names.)" (see OED-3, s.v. "lodge" [4b] and the related meaning lodge ((1)) [4b] in DCHP-1). Compounds like seniors lodge are common in Canadian English (see Chart 1). Seniors lodge is a form used mostly from Ontario to BC, with a heavy concentration in Alberta (see Chart 1). Seniors' lodge is less common, although usage guides and grammar books would recommend the apostrophe as marking the possessive; however it is today often dropped in combinations where the first term is a plural noun marking an affiliation (e.g. "teachers union", "veterans club", etc.).
See also COD-2, s.v. "lodge" noun (3), which is marked "Cdn", "especially" in proper names.
See also: lodge ((1)) def. 4b
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Chart 1: Internet Domain Search, 3 Mar. 2016
Chart 2: Regional Domain Search, 3 Mar. 2016