cuirass

the word 'cuirass' entered english in the late middle ages from the old french 'cuirasse', which itself derived from the vulgar latin 'coriacea', meaning '(garment) of leather'. this latin form originates from 'corium', the latin word for 'leather' or 'hide'. the semantic evolution is direct: the original protective gear was made of boiled leather before metal became standard. thus, the term's core logic moves from the material (leather) to the functional item (body armor) made from that material, a meaning preserved into the modern era for both historical armor and biological analogies.

this word is a loanword adopted as a simplex unit from french. it does not contain separable, meaningful morphemes within modern english spelling.