Tandem

Tandem, or in tandem, is an arrangement in which a team of machines, animals or people are lined up one behind another, all facing in the same direction.^[1]

The original use of the term in English was in tandem harness,^{[citation needed]} which is used for two or more draft horses, or other draft animals, harnessed in a single line one behind another, as opposed to a pair, harnessed side by side, or a team of several pairs. The tandem harness allows additional animals to provide pulling power for a vehicle designed for a single animal.

The English word tandem derives from the Latin adverb tandem, meaning at length or finally.^[2] It is a word play, using the Latin phrase (referring to time, not position) for English "at length, lengthwise".^[3]

Tandem bicycles are named for their tandem seating, a more common arrangement than side-by-side "sociable" seating. Tandem can also be used more generally to refer to any group of persons or objects working together, not necessarily in line.^[1]