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The Hornets were supposed to be the Spirit, while the Grizzlies were almost named the Mounties. Why is a team in Los Angeles nicknamed the Lakers, and what’s a team called the Jazz doing in Utah? As the NBA season tips off tonight, here’s the story behind the nicknames of all 30 teams.

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Boston Celtics
Team owner Walter Brown personally chose Celtics over Whirlwinds, Olympians, and Unicorns (yes, Unicorns) as the nickname for Boston’s Basketball Association of America team in 1946. Despite the warnings of one of his publicity staffers, who told Brown, “No team with an Irish name has ever won a damned thing in Boston,” Brown liked the winning tradition of the nickname; the New York Celtics were a successful franchise during the 1920s.

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http://www.mentalfloss.com/blogs/archives/38838