One gross is a unit of measurement, for countable items. It is equal to 12 dozen, or 144 pieces. In the same manner, a dozen gross, or 1728 items is called great gross. Small gross or great hundred is used to refer to ten dozen items. If a shop is advertising to sell a product "en gros", this means that it will sell larger quantities.

The term dates from the early 15th century, from the Old French "grosse douzaine", "large dozen”. A gross may be abbreviated as "gr" or "gro".

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