A loud, hearty, unrestrained laugh or the act of laughing in this boisterous way.
Possibly from Scottish origin, perhaps imitative in nature; first recorded in English in the 17th century, related to onomatopoeia for loud laughter.
Guffaw is one of English's most delightfully weird words—it sounds exactly like what it means, and linguists believe it's purely imitative, created because people needed a word that sounded like big belly laughs.
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