語源はwear,investと同じ。派生語源はauthorise, endow, 特定の衣服からの象徴。
The King hath yesterday, in Council, declared his resolution of setting a fashion for clothes .... It will be a vest, I know not well how; but it is to teach the nobility thrift. [Pepys, "Diary," Oct. 8, 1666]Louis XIV of France is said to have mocked the effort by putting his footmen in such vests.