buckle

Definitions

General English

Aviation

  • noun a metal part of a belt used for joining the two ends together
  • verb to bend out of shape because of heat or force

Cars & Driving

  • noun the locking metal clasp of a seat belt

Construction

  • The distortion of a structural member such as a beam or girder under load. This condition is brought on by lack of uniform texture or by irregular distribution of weight, moisture, or temperature.
  • A flaw or distortion on the surface of a sheet of material, particularly asphalt roofing.
  • A thin tree branch bent in the shape of a "U" to fasten thatch onto roofs.

Origin & History of “buckle”

English acquired buckle via Old French boucla from Latin buccula ‘cheek strap of a helmet’. This was a diminutive form of Latin bucca ‘cheek’ (source of French bouche ‘mouth’), which gave English the anatomical term buccal ‘of the cheeks’ (19th c.), and some have speculated is related to English pock. The notion of ‘fastening’ implicit in the Latin word carried through into English.

As well as ‘cheek strap’, Latin buccula meant ‘boss in the middle of a shield’. Old French boucle adopted this sense too, and created the derivative boucler, originally an adjective, meaning (of a shield) ‘having a central boss’. English borrowed this as buckler ‘small round shield’ (13th c.).

The verb buckle was created from the English noun in the late 14th century, but the sense ‘distort’, which developed in the 16th century, comes from French boucler, which had come to mean ‘curl, bulge’. also from the French verb is bouclé ‘yarn with irregular loops’ (19th c.).
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