A simpleton. Probably of Scottish origin.

1

1825.  Sort of a naiteral too, I guess; rather a gump, hey?—John Neal, ‘Brother Jonathan,’ ii. 42. (N.E.D.)

2

1846.  

        Tell ye jest the eend I ’ve come to
  Arter cipherin’ plaguy smart,
An’ it makes a handy sum, tu,
  Any gump could larn by heart.
Lowell, ‘Biglow Papers,’ No. 1.    

3

1851.  I wouldn’t be a gump, ef I was you.—J. J. Hooper, ‘Adventures of Captain Simon Suggs,’ &c., p. 179.

4

1856.  He ’s the consarndest old gump tew t’ ever was—no intellectibility at all.—Whitcher, ‘The Widow Bedott Papers,’ No. 9.

5

1858.  Then I, like a gump, would choke up more, and carry my heart in my mouth for the next hour, wholly unable to speak a word!—Knick. Mag., li. 371 (April).

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