Canadian

google

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mid 19th century: apparently from Canada.

wiktionary

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From Canada(noun) +‎ -ian(suffix forming adjectives and nouns).

A name of uncertain origin. The city and town names are after the river.

etymonline

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Canadian (adj.)

"pertaining to Canada," 1560s; see Canada. Also as a noun, "native or inhabitant of Canada" (1759).