1a n. — Hockey
a beard whose growth is started at the beginning of the NHL hockey playoffs by a player competing for the Stanley Cup.
Type: 4. Culturally Significant — The tradition is purported to have begun in the late 1970s or early 1980s (see the 1983 and 2013 quotations). According to some sources (see, e.g. the 2011 quotation from a US magazine), the tradition was started in 1980 by the New York Islanders. While playoff beards may have initially been grown by players, currently both fans and players partake in the tradition (see meaning 1b). Playoff beards may be grown for superstitious reasons, as is often the case among players. The reasoning goes, if a player shaves his beard before his team wins the cup, they will not win it this year (see the 2011 quotation).
Internet domain searches show that the term is most frequent in Canada (see Chart 1).
See also: hockey playoff
1b n. — Hockey
the beard of a fan whose team is competing in the Stanley Cup Playoffs (see meaning 1a).
Type: 4. Culturally Significant — Playoff beards were originally grown by participating players, but more recently fans have participated in the tradition. Fans may grow beards for superstitious reasons or as part of charitable fundraising initiatives.
2 n.
a beard that is grown at the start of some difficult process or project.
Type: 3. Semantic Change — Due to the importance of hockey to large sections of the Canadian population, the semantic generalization of a fairly recent meaning to other, non-hockey domains is a predictable event (see, e.g. game seven.)
See also: game seven (meaning 2)
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Chart 1: Internet Domain Search, 17 Jul. 2013