Waistcoats, commonly referred to as vests today, with respect to a three-piece suit, are a classic part of a gentleman's clothing. Often today, although the terms "waistcoat" and "vest" are synonyms, the former is often used in reference to the more traditional formal or semi-formal low-cut style such as that sold by Ralph Lauren. "Vest", by contrast, is frequently used to refer to the taller component of a a three-piece suit, and that is often mistakenly worn at weddings despite its incongruity being an affront to the pomp and ceremony the event is often built upon.
I told him that dirt in it's your dirt. What's your dirt doin' in his ditch?