Definition of "interrogative"

The regular place of the interrogative word, of whatever kind, is at the beginning of the sentence, or as near it as possible.

1877, William Dwight Whitney, Essentials of English Grammar for the Use of Schools, §470

Thus speaking, the good man regarded his lady with an interrogative look. "I do n't know, dear!" she replied kindly, and sighing again.

1847, Charles Sealsfield, Rambleton: A Romance of Fashionable Life in New-York during the Great Speculation of 1836, page 127

There be five manner of points and divisions most used among cunning men; the which if they be well used, make the sentence very light and easy to be understood, both to the reader and hearer: and they be these, virgil,—come,—parenthesis,—plain point,—interrogative.

1824, J. Johnson, Typographia

Whoever introduced the several points, it seems that a full-point, a point called come, answering to our colon-point, a point called virgil answering to our comma-point, the parenthesis-points and interrogative-point, were used at the close of the fourteenth, or beginning of the fifteenth century.

1842, F. Francillon, An Essay on Punctuation, page 9

"Who are you, sir, and what is your business?" demanded the Marquis... "That is a fair interrogative, my lord," answered Dalgetty.

1819, Sir Walter Scott, A Legend of Montrose, section XII