Hoop \Hoop\, v. i. [OE. houpen; cf. F. houper to hoop, to shout; -- a hunting term, prob. fr. houp, an interj. used in calling. Cf. Whoop.]

1. To utter a loud cry, or a sound imitative of the word, by way of call or pursuit; to shout. [Usually written whoop.]

[1913 Webster]

2. To whoop, as in whooping cough. See Whoop. [1913 Webster]

Hooping cough. (Med.) See Whooping cough. [1913 Webster]

Source: The Collaborative International Dictionary of English v.0.48
 

Hoop \Hoop\, v. i. [OE. houpen; cf. F. houper to hoop, to shout; -- a hunting term, prob. fr. houp, an interj. used in calling. Cf. Whoop.]

1. To utter a loud cry, or a sound imitative of the word, by way of call or pursuit; to shout. [Usually written whoop.]

2. To whoop, as in whooping cough. See Whoop.

Hooping cough. (Med.) See Whooping cough.

Source: Webster's Revised Unabridged Dictionary (1913)