A derivative may end up more specific in meaning and application than it started out as being. Such is the case with the word 'vest'. It started out as the Latin word 'vestimentum', whose original meaning took in any article of clothing. But the process of specialization of meaning took effect. The consequence was the narrower, stricter meaning of the noun 'vest' as a sleeveless garment meant to be worn under the coat of a business suit.