a. [f. CRACK v. + JAW sb.] Fit to crack the jaws; difficult to pronounce.

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1826.  Disraeli, Viv. Grey, V. xiii. 237. A Polish nobleman, a Count somebody; I never can remember their crack-jaw names.

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1862.  H. Marryat, Year in Sweden, I. 232. The names are far too crackjaw.

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1886.  G. Allen, Maimie’s Sake, v. Your outlandish crack-jaw foreigner lingo.

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