brassiere

The French word 'bras' has meant arm since the 12th century, drawing from Latin 'bracchium' and ultimately from Greek 'brakhion,' the upper arm bone that lends its name to the brachial artery. Old French 'brassière' first appears in the 14th century as protective armor: a guard for the forearm worn in battle. The word was built from 'bras' with the suffix '-ière,' marking a thing belonging to the arm. Nobody designing a plate gorget in 1350 could have imagined where the word was headed.

By the 18th century 'brassière' had shifted meaning in France from armor to a softer constraint. It denoted a life-preserver or rescue harness worn across the chest and under the arms, and seamstresses also applied it to a baby's fitted vest, a small garment that held the torso snug. The pattern of meaning running from the arm upward to the chest was now established. French fashion vocabulary traveled easily to Britain and America through the clothing trade, carried in fabric samples and catalogue copy.

The English-language borrowing for a women's undergarment appears in print by 1904, when American department stores began advertising the garment by name. The New York Times used 'brassiere' that year to distinguish the new fitted bodice support from older corsets and chemises, and Vogue magazine adopted it readily through the 1900s, cementing the spelling and register. The garment was part of a wider movement away from full-torso corsets toward lighter, more segmented underclothing. The arm guard had completed its long migration.

The abbreviated 'bra' appeared in print by the 1930s and became the dominant spoken form in most English dialects by mid-century. The longer 'brassiere' survived in formal catalogues, medical writing, and legal documents. Beneath the modern garment sits the ghost of a medieval arm guard, a reminder that the body's anatomy has always shaped the vocabulary of dress: the part named first eventually gives its name to the whole.