A nail of a large size.

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1770.  A Moses Boat, with the Larboard Gunwale broke, and mended with Board Nails amidships.—Advt., Mass. Gazette, Jan. 29.

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1833.  Mr. Van Buren marched out of the room, looking as though he could bite a board nail off.—Seba Smith, ‘Major Jack Downing,’ p. 226 (1860).

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1866.  And then father would look gritty enough to bite a board-nail off.—Ib., ‘’Way Down East,’ p. 62.

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1867.  

        In business strict, to bring the balance true
He had been known to bite a fig in two,
And change a board-nail for a shingle-nail.
J. R. Lowell, ‘Fitz-Adam’s Story.’    

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