A butler sink is a type of sink often used as a kitchen or utility sink. While most sinks are built to be set into a countertop, a butler sink is cast in the form of a full box, to sit independently on low table or counter. They are often larger and more sturdy than the average sink, and are traditionally made from stoneware.
The name 'butler sink' dates from a time when a butler was not just a personal valet , but was the head servant in the household, with particular duties in overlooking meals and the wine cellar. The butler sink, therefore, might be the primary sink in a household, utilitarian in form and function. The Butler's pantry might have another sink, a special one lined with soft lead to reduce the risk of chipping when washing delicate china; this was not referred to as the 'butler sink', however.
Butler sinks are also called Belfast sinks, farmhouse sinks or French farmhouse sinks. One expert on sinks relates that these are actually very specific types of butler sinks. In the 1600s Belfast's city sanitation officer mandated an overflow prevention drain (much as you find in every bathroom sink nowadays) be present in all sinks, while the London official mandated sinks without overflow drains. The London butler sinks have come to be called simply butler sinks, while the Belfast butler sinks are now called Belfast sinks.
In the 1800s butler sinks made from highly refined French clay became popular, as they could have thinner sides and more artistic construction. These are generally known as French farmhouse sinks. It should be noted, however, that other types of sinks may also be called farmhouse sinks; the term usually denotes a large, self-supporting sink, but it may take any form, and need not be box-like.
Butler sinks were in common usage until about a hundred years ago, when they finally fell out of fashion. They were often relegated to utility rooms or used as planters for the garden. They have been out of general use for so long that they have become fashionable as an 'antique' look, and modern butler sinks are now sold by many high-end sink companies.