1 n. — historical, West Coast, British Columbia and Pacific Northwest
a person or people; (one's) people.
Type: 1. Origin — Tillicum is a lexical transfer from Chinook Jargon, a pidgin language that was used in British Columbia and the Pacific Northwest to facilitate communication between trade communities. George Lang (2008: 32, 49), in Making Wawa: The Genesis of Chinook Jargon, suggests it may have been based on a pre-contact trade language centred on the mouth of the Columbia River. It is based on Lower Chinook, Nootka, French and English, with some influence from other Aboriginal languages (see Canadian Encyclopedia reference, s.v. "Chinook Wawa"). DARE, s.v. "tillicum", lists an Oregon quotation with the variant "fillicum" as the earliest American use, dated to 1843. According to OED-3 (s.v. "tillicum"), tillicum derives from the Chinook word tilxam, meaning 'village'. Though the term may be used to denote people in general, it may also take on a sense of belonging or camaraderie, a meaning similar to 'someone of my band or people' (see, e.g., the 2002 quotation). This interpretation likely led to the semantic extension to 'friend' or 'buddy', as shown in meaning 2. Tillicum is most frequently used in Canada (see Chart 1), with regional hits being focused in BC (see Chart 2).
See also: Chinook Jargon
2 n. & adj. — rare
friend, buddy, pal.
Type: 1. Origin — See meaning 1. The term has fallen out of use since the mid-20th century, when Chinook terms were still widely known, especially in rural regions (see, e.g., the 1948 quotation). Today the term is often used, if it is used at all, to humorous effect (see the 2009 quotation).
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Chart 1: Internet Domain Search, 15 Jul. 2014
Chart 2: Regional Domain Search, 15 Jul. 2014