Foolishly impetuous.

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1824.  What a brash raggald! Craven dialect. (N.E.D.)

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1837.  Strannger thar’s as brash as a new hound in a b’ar fight. (Note) Brash,—rash, headstrong, over-valiant.—R. M. Bird, ‘Nick of the Woods,’ i. 177 (Lond.).

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