Definition of halloo

• n. - A loud exclamation; a call to invite attention or to incite a person or an animal; a shout.
• v. i. - To cry out; to exclaim with a loud voice; to call to a person, as by the word halloo.
• v. t. - To encourage with shouts.
• v. t. - To chase with shouts or outcries.
• v. t. - To call or shout to; to hail.
• n. - An exclamation to call attention or to encourage one.