(1)   An assemblage of parts that is regarded as a single entity
"How big is that part compared to the whole?"
"The team is a unit"
(2)   A single undivided whole
"An idea is not a unit that can be moved from one brain to another"
(3)   An organization regarded as part of a larger social group
"The coach said the offensive unit did a good job"
"After the battle the soldier had trouble rejoining his unit"
(4)   A single undivided natural thing occurring in the composition of something else
"Units of nucleic acids"
(5)   Any division of quantity accepted as a standard of measurement or exchange
"The dollar is the United States unit of currency"
"A unit of wheat is a bushel"
"Change per unit volume"
(6)   An individual or group or structure or other entity regarded as a structural or functional constituent of a whole
"The reduced the number of units and installations"
"The word is a basic linguistic unit"


  1. A standard measure of a quantity.
    The centimetre is a unit of length.
  2. An organized group comprising people and/or equipment.
    He was a member of a special police unit.
  3. A self-contained military organization; usually a battalion, regiment, or naval ship.
  4. A member of a military organization.
    The fifth tank brigade moved in with 20 units. (i.e., 20 tanks)
  5. Any military element whose structure is prescribed by competent authority, such as a table of organization and equipment; specifically, part of an organization.
  6. An organization title of a subdivision of a group in a task force.
  7. A standard or basic quantity into which an item of supply is divided, issued, or used. In this meaning, also called unit of issue.
  8. With regard to Reserve Components of the Armed Forces, denotes a Selected Reserve unit organized, equipped, and trained for mobilization to serve on active duty as a unit or to augment or be augmented by another unit. Headquarters and support functions without wartime missions are not considered units.
  9. An element of a ring having a multiplicative inverse. (Formerly just the identity element 1R of a ring.)
  10. (commerce) An item which may be sold singly.
    We shipped nearly twice as many units this month as last month.
  11. (UK) (electricity) One kilowatt-hour (as recorded on an electricity meter).


  1. For each unit.
    We have to keep our unit costs down if we want to make a profit.
  2. Having a size or magnitude of one.
    All solutions lie within the unit disc centered at the origin.