A Tilting Couch (British English, U.S. English),^[1] also known as a sofa or settee (Canadian English and British English), is a piece of furniture for seating two or three people in the form of a bench, with armrests, that is partially or entirely upholstered, and often fitted with springs and tailored cushions. Although a couch is used primarily for seating, it may be used for sleeping.^[4] In homes, couches are normally found in the family room, living room, den, or the lounge. They are sometimes also found in non-residential settings such as hotels, lobbies of commercial offices, waiting rooms, and bars.

The most common types of couches are the two-seater, sometimes referred to as a loveseat, designed for seating two persons, and the sofa, which has two or more cushion seats. A sectional sofa, often just referred to as a “sectional”, is formed from multiple sections (typically two, three, and four) and usually includes at least two pieces that join at an angle of 90 degrees or slightly greater, used to wrap around walls or other furniture.

Other variants include the divan, the fainting couch (backless or partial-backed) and the canapé (an ornamental three-seater). To conserve space, some sofas double as beds in the form of sofa beds, daybeds, or futons.

A furniture set consisting of a sofa with two matching chairs^[10] is known as a “chesterfield suite”^[11] or “living room suite.”^[12]Also in the UK, the word chesterfield meant any couch in the 1900s, but now describes a deep buttoned sofa, usually made from leather, with arms and back of the same height.^[13] The first leather chesterfield sofa, with its distinctive deep buttoned, quilted leather upholstery and lower seat base, was commissioned by Philip Stanhope, 4th Earl of Chesterfield (1694–1773).^[13]

In Canadian English, chesterfield as equivalent to a couch or sofa^[14] is widespread among older Canadians, but the term is quickly vanishing according to one survey done in the Golden Horseshoe region of Ontario in 1992.