Noun

(en noun)

(sciences) A standard measure of a quantity.

The centimetre is a unit of length.

The number one.

This pill provides 500 units of Vitamin E.

An organized group comprising people and/or equipment.

He was a member of a special police unit .

(military, informal) A member of a military organization.

The fifth tank brigade moved in with 20 units .'' (''i.e., 20 tanks )

(US, military) Any military element whose structure is prescribed by competent authority, such as a table of organization and equipment; specifically, part of an organizationJoint Publication 1-02 U.S. Department of Defense Dictionary of Military and Associated Terms; 12 April 2001 (As Amended Through 14 April 2006). .

(US, military) An organization title of a subdivision of a group in a task force.

(US, military) A standard or basic quantity into which an item of supply is divided, issued or used. In this meaning, also called unit of issue.

(US, military) 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.

(algebra) An element of a ring having a multiplicative inverse. (Formerly just the identity element 1_R of a ring.)

(geology) A volume of rock or ice of identifiable origin and age range that is defined by the distinctive and dominant, easily mapped and recognizable petrographic, lithologic or paleontologic features (facies) that characterize it.

(commerce) An item which may be sold singly.

We shipped nearly twice as many units this month as last month.

(UK, electricity) One kilowatt-hour (as recorded on an electricity meter).

(Australia, New Zealand) a measure of housing equivalent to the living quarters of one household, an apartment where a group of apartments is contained in one or more multi-storied buildings or a group of dwellings is in one or more single storey buildings, usually arranged around a driveway.

(historical) A gold coin of the reign of James I, worth twenty shillings.

(Camden)

Noun

(uncountable) The quality of being different.

(countable) A characteristic of something that makes it different from something else.

* {{quote-magazine, title=Towards the end of poverty

, date=2013-06-01, volume=407, issue=8838, page=11, magazine=(The Economist) citation , passage=But poverty’s scourge is fiercest below $1.25 (the average of the 15 poorest countries’ own poverty lines, measured in 2005 dollars and adjusted for differences in purchasing power): people below that level live lives that are poor, nasty, brutish and short.}}

(countable) A disagreement or argument.

We have our little differences , but we are firm friends.

* Shakespeare

What was the difference ? It was a contention in public.

* T. Ellwood

Away therefore went I with the constable, leaving the old warden and the young constable to compose their difference as they could.

(countable, uncountable) Significant change in or effect on a situation or state.

* 1908 , (Kenneth Grahame), (The Wind in the Willows)

The line of the horizon was clear and hard against the sky, and in one particular quarter it showed black against a silvery climbing phosphorescence that grew and grew. At last, over the rim of the waiting earth the moon lifted with slow majesty till it swung clear of the horizon and rode off, free of moorings; and once more they began to see surfaces—meadows wide-spread, and quiet gardens, and the river itself from bank to bank, all softly disclosed, all washed clean of mystery and terror, all radiant again as by day, but with a difference that was tremendous.

(countable) The result of a subtraction; sometimes the absolute value of this result.

(obsolete) Choice; preference.

* Spenser

That now be chooseth with vile difference / To be a beast, and lack intelligence.

(heraldry) An addition to a coat of arms to distinguish two people's bearings which would otherwise be the same. See augmentation and cadency.

(logic) The quality or attribute which is added to those of the genus to constitute a species; a differentia.

(logic circuits) A Boolean operation which is TRUE when the two input variables are different but is otherwise FALSE; the XOR operation ($\backslash scriptstyle\; A\; \backslash overline\; B\; +\; \backslash overline\; A\; B$).

(relational algebra) the set of elements that are in one set but not another ($\backslash scriptstyle\; A\; \backslash overline\; B$).