Merriam-Webster's Collegiate® Dictionary, 11th Edition
COAT
I. noun
Usage: often attributive
Etymology: Middle English cote, from Anglo-French, of Germanic origin; akin to Old High German kozza coarse wool mantle
Date: 14th century
1. an outer garment worn on the upper body and varying in length and style according to fashion and use, something resembling a coat, the external growth on an animal, a layer of one substance covering another , coated adjective coatless adjective
II. transitive verb
Date: 14th century
to cover with a coat, to cover or spread with a finishing, protecting, or enclosing layer, coater noun