To perceive, to imagine.

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1847.  He always conceited I was a sort of a sister to him!—T. B. Thorpe, ‘The Big Bear of Arkansas: Billy Warwick’s Courtship and Wedding,’ p. 103 (Phila.).

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1856.  If you do conceit that you ’ve discovered something of the sort, the natives will soon argue you down flat on it.—Knick. Mag., xlviii. 505 (Nov.).

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1878.  As soon as he conceited what was up, he gathered a dornick, and was just drawin’ back to send the strange dog where they’s no fleas, when the stranger saw him and went one better.—J. H. Beadle, ‘Western Wilds,’ p. 185.

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