As a noun, chops once meant jaws. This sense of the word survives in locutions such as “to lick one’s chops.” Topographically, chops refers to a narrow passage or entryway, typically a forbidding one. This might be an alpine gap, but the term, like mouth, occurs most often in nautical contexts. Major Robert Rogers, leading a little armada of bateaux along the north shore of Lake Ontario in September 1760, describes entering “the chops of a river, called by the Indians the Grace of Man.” James Sullivan, in his History of the District of Maine, mentions “the Chops of Merrymeeting Bay—a strait where the ebbing and flowing tides are alike hazardous to navigation.” This place is now known to locals simply as the Chops. In Britain, the southern end of the English Channel has long been called “the Chops of the Channel.” It, too, is famously hazardous to navigation.

Franklin Burroughs