n.
an alley in an urban area.
Type: 2. Preservation — Laneway may be a preservation from Irish English. The 1873 quotation, from the Canadian publication The True Witness and Catholic Chronicle, is a reprint from an Irish newspaper. The earliest OED-3 quotation is dated 1882, from London, England (s.v. "lane-way"). Furthermore, of the 30 instances of the term with this meaning in the London Times Archives, 24 were about Ireland, the earliest of which dated to 1858 (21 of these had an Irish dateline). Only six were not about Ireland, the earliest, isolated citation dating from 1928, with the five subsequent citations all dating from after 1980. EDD labels its entry for laneway as County Mayo, Ireland (see EDD, s.v. "lane" [1.] in comp. [2]). Laneway continues to enjoy a high prevalence in Ireland, although internet searches show that the term is today more prevalent in Canada, and quite frequent in Australia (see Chart 1).
In 19th-century Ireland, laneway designated any type of alley or lane, whether in the city or country. In Canada, over the course of the 20th century, the term has undergone a semantic change, and now denotes a narrow city street (a back alley); see the 1923 quotation from Toronto. It is therefore both a Preservation from Irish English (Type 2) and a Semantic Change in Canadian English (Type 3).
COD-2, s.v. "laneway" [2], marks the meaning as "Cdn".
See also: laneway house
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Chart 1: Internet Domain Search, 15 Aug. 2012