n. — predominantly Prairies, (children's) hockey, historical
a piece of frozen horse manure used as a hockey puck.
Type: 5. Frequency — In Canada, road apple appears to have undergone semantic change from the more general meaning of "horse manure" (see DARE, s.v. "road apple"). The term is virtually restricted to Canada (see Chart 1), with cultural significance because of its connection to the Canadian love of hockey.
See also COD-2, s.v. "road apple" (2), which is marked "Cdn hist", and DARE, s.v. "road apple".
See also: hockey puck shinny (meaning 1a)
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Chart 1: Internet Domain Search, 15 Jan. 2014