An inflated opinion of oneself. The 1805 quotation needs a comment.

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1805.  A Brown Steer, having “what they call the Big Head,” advertised in the Lancaster (Pa.) Intelligencer, Dec. 3.

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1853.  Mayor How’s ungallant attack upon the little boys of our city is a weak emanation of a “big head.”Daily Morning Herald, July 2 (St. Louis).

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1853.  Were I to use a Western term, I would say “they were troubled with a big head.”—Brigham Young, Dec. 5: ‘Journal of Discourses,’ i. 338.

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1855.  They had got the big head, that is, their heads were larger than the substances would sustain.—H. C. Kimball at the Mormon Tabernacle, Feb. 25: id., iii. 162.

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1856.  We will send men to the Missouri river who understand the right management of affairs, and will send them in the speediest conveyances, so that they may not get the “big head” before they arrive there, and then they may be able to do as we tell them…. They need to be careful or they will have the “big head” and become as dead and devoid of the Spirit as old pumpkins.—Brigham Young, Nov. 2: id., iv. 69.

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1896.  “I’ll tell you what’s the matter with her!” interrupted Emarine. “She’s got the big-head.”—Ella Higginson, ‘Tales from Puget Sound,’ p. 100.

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