Definitions of unit:

• noun:   a single undivided whole

  Example: "An idea is not a unit that can be moved from one brain to another"

• noun:   an organization regarded as part of a larger social group

  Example: "The coach said the offensive unit did a good job"

• noun:   a single undivided natural thing occurring in the composition of something else

  Example: "Units of nucleic acids"

• noun:   an individual or group or structure or other entity regarded as a structural or functional constituent of a whole

  Example: "The reduced the number of units and installations"

• noun:   any division of quantity accepted as a standard of measurement or exchange

  Example: "The dollar is the United States unit of currency"

• noun:   an assemblage of parts that is regarded as a single entity

  Example: "The team is a unit"