U.S. slang. = BOOMER1; one who works up a ‘boom’; a speculator.

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1879.  Nation, 9 Oct., 236. The trickery and usurpation … of the leading boomster.

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1884.  S. E. Dawson, Hand-bk. Canada, 331. The speculators, called, in vivid Western parlance, boomsters.

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