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lantern jaw

American  

noun

  1. a distinctly protruding, often wide lower jaw.

  2. a long, thin jaw.

lantern jaw British  

noun

  1. a long hollow jaw that gives the face a drawn appearance

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of lantern jaw

First recorded in 1690–1700; so called from the fancied resemblance of the face to the shape of a lantern

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.