from The American Heritage® Dictionary of the English Language, 4th Edition
- n. A hearty, boisterous burst of laughter.
- intransitive v. To laugh heartily and boisterously.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. A boisterous laugh
- v. To laugh boisterously.
from the GNU version of the Collaborative International Dictionary of English
- n. A loud burst of laughter; a horse laugh.
from The Century Dictionary and Cyclopedia
- To laugh loudly and coarsely or rudely.
- n. A loud, rude burst of laughter; a horse-laugh.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- v. laugh boisterously
- n. a burst of deep loud hearty laughter
Probably imitative.(American Heritage® Dictionary of the English Language, Fourth Edition)
Probably onomatopoetic. (Wiktionary)