Origin of buckle

1300–50; Middle English bocle < Anglo-French bo(u)cle, bucle < Latin buc(c)ula cheekpiece (of a helmet), strip of wood, etc., resembling a cheekpiece, equivalent to bucc(a) cheek + -ula -ule
Related formsbuck·le·less, adjectivere·buck·le, verb, re·buck·led, re·buck·ling.

Synonyms for buckle

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

British Dictionary definitions for buckle up

buckle

noun

a clasp for fastening together two loose ends, esp of a belt or strap, usually consisting of a frame with an attached movable prong
an ornamental representation of a buckle, as on a shoe
a kink, bulge, or other distortiona buckle in a railway track

verb

to fasten or be fastened with a buckle
to bend or cause to bend out of shape, esp as a result of pressure or heat

Word Origin for buckle

C14: from Old French bocle, from Latin buccula a little cheek, hence, cheek strap of a helmet, from bucca cheek
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

Word Origin and History for buckle up

buckle

n.

"spiked metal ring for holding a belt, etc., c.1300, bukel, from Old French bocle "boss (of a shield)," then "shield," then by further extension "buckle, metal ring," (12c., Modern French boucle), from Latin buccula "cheek strap of a helmet," in Late Latin "boss of a shield," diminutive of bucca "cheek" (see bouche).

Boucle in the middle ages had the double sense of a "shield's boss" and "a ring"; the last sense has alone survived, and it metaph. developed in the boucle de cheveux, ringlets. [Kitchin]

buckle

v.2

"distort, warp, bend out of shape" 1520s, bokelen "to arch the body," from Middle French boucler "to bulge," from Old French bocler "to bulge," from bocle "boss of a shield" (see buckle (n.)). Meaning "bend under strong pressure" is from 1590s (figurative from 1640s) . Related: Buckled; buckling.

buckle

v.1

late 14c., bokelen, "to fasten with a buckle," from buckle (n.). Related: Buckled; buckling. To buckle down "apply effort, settle down," (1874) is said to be a variant of knuckle down (see knuckle).

Online Etymology Dictionary, © 2010 Douglas Harper

Idioms and Phrases with buckle up

buckle up

Fasten a seat belt, as in All the children must learn to buckle up as soon as they get in a car. This term came into wide use in the second half of the 1900s, when seat belts became mandatory automobile equipment. Earlier they had been used mainly in airplanes.

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