n. — Administration
a postal facility serving a heavily populated area that may be far from the nearest post office, often in urban areas.
In the US, the term is synonymous with post office and in Canada, many use this technical term in a similar way. Canada was not the first nation to use the term postal station, although the precise meaning of a kind of sub post office that does not offer any services to customers but is needed for postal delivery in densely populated areas, may be. Currently, postal station is most prevalent in Canada according to internet domain searches (see Chart 1), yet not sufficiently more frequent to declare it a Canadianism. Likewise, the semantic distinction seems to be too narrow and technical to consider it one of the six types of Canadianisms (see Dollinger 2015c).
See also COD-2, s.v. "postal station", which is marked "Cdn", an assessment that we do not share.
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Chart 1: Internet Domain Search, 4 Oct. 2012