Merriam-Webster's Collegiate® Dictionary, 11th Edition
BUCKLE
I. noun
Etymology: Middle English bocle, from Anglo-French, boss of a shield, buckle, from Latin buccula, diminutive of bucca cheek
Date: 14th century
a fastening for two loose ends that is attached to one and holds the other by a catch, an ornamental device that suggests a buckle, a crisp curl,
II. verb (buckled; buckling)
Date: 14th century
transitive verb to fasten with a buckle, to prepare with vigor, to cause to bend, give way, or crumple, intransitive verb to become fastened with a buckle, to apply oneself with vigor, to bend, heave, warp, or kink usually under the influence of some external agency , collapse , to give way ; yield ,
III. noun
Date: circa 1876
a product of buckling ; bend , fold , a coffee cake baked with berries and a crumbly topping