Dozen is another word for the number twelve. It originates from the Latin word duodecim. The dozen may be one of the earliest primitive groupings, perhaps because there are approximately a dozen cycles of the moon in a cycle of the sun. The use of twelve as a base number, known as the duodecimal system, probably originated in Mesopotamia. Twelve dozen (12² = 144) are known as a gross. Twelve gross (12³ = 1,728) is called a great gross, a term most often used when shipping or buying items in bulk. A great hundred is 120 or ten dozen (a dozen for each finger on both hands).

The dozen is convenient because its multipliers and multiples are convenient: 12 = 3 × 2 × 2, and 360 = 30 × 12. The French word douzaine means "about twelve" and is part of a family of words with similar meanings, e.g. vingtaine - "about 20" centaine - "about 100" etc. A baker's dozen, also known as a long dozen, is thirteen.

See also

• Base twelve.
• Number 12
• Baker's dozen

numbers | Units based on multiples of 12

Dusin | Dutzend | Docena | Tucat | Dozijn | ダース | Dusin | Tuzin | Дюжина | Ducat | Kappalemitta | Dussin | Düzine