Mathematics, Sciences Oneness, singularity, seen as a component of a whole number; a magnitude of one.
Number, we define, to be, a certayne Mathematicall Sũme, of Vnits. [Note the worde, Vnit, to expresse the Greke Monas, & not Vnitie: as we haue all, commonly, till now, vsed.]1570, John Dee, in H. Billingsley (trans.) Euclid, Elements of Geometry, Preface
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Sciences A standard measure of a quantity or magnitude.
The centimetre is a unit of length.
The pound sterling is a unit of currency.
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Computing, Engineering, Mathematics, Natural sciences, Physical sciences, Sciences A basic, self-contained component or module that performs a specific function inside a computer system.
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The number one.
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Abbreviation, Ellipsis Ellipsis of international unit.
This pill provides 500 units of Vitamin E.
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An organized group comprising people or equipment.
He was a member of a special police unit.
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Education A course, lesson, or section of a curriculum covering a particular topic or skill.
We're starting a new unit on photosynthesis next week.
We shipped nearly twice as many units this month as last month.
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Australia, New Zealand, UK, US Any piece of equipment, such as an appliance, power tool, stereo system, computer, tractor, or machinery.
This air-conditioner is the most efficient unit we sell.
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Business, Commerce, Retail A structure used to display goods for sale (usually containing shelves, pegs or hooks)
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Australia, New Zealand, US 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.
The new apartment complex will have 50 units.
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Medicine, Sciences A quantity of approximately 517 milliliters (1.1 U.S. pints) of blood.
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Government, Military, Politics, WarUS Any military element whose structure is prescribed by competent authority, such as a table of organization and equipment; specifically, part of an organization.
Government, Military, Politics, WarUS A standard or basic quantity into which an item of supply is divided, issued, or detailed.
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Government, Military, Politics, WarUS 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.
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Algebra, Mathematics, Sciences The identity element, the neutral element.
An element 𝑒 of 𝑆 such that 𝑒𝑥 = 𝑥 = 𝑥𝑒 for all 𝑥 ∈ 𝑆 is called a unit element. (When the law of composition is written additively, the unit element is denoted by 0, and is called a zero element.)2005, Serge Lang, Algebra, 3rd edition, Springer, →ISBN, page 3:
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Algebra, Mathematics, Sciences An element having an inverse, an invertible element; an associate of the unity.
Let 𝐴 be an arbitrary integral domain. We say that an element 𝑎 ∈ 𝐴 is invertible or is a unit of 𝐴 if it has an inverse in 𝐴; in ℤ the units are ±1, […]1990, A. I. Kostrikin, I. R. Shafarevich, editors, Algebra I, Springer, →ISBN, page 22:
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Category theory, Computing, Engineering, Mathematics, Natural sciences, Physical sciences, Sciences In an adjunction, a natural transformation from the identity functor of the domain of the left adjoint functor to the composition of the right adjoint functor with the left adjoint functor.
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Geography, Geology, Natural sciences 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.
For example, the Moenkopi Formation was named for the small settlement of Moenkopi, Arizona where the formation was first defined as being a separate unit from the rocks above and beneath it.2012, Chinle Miller, In Mesozoic Lands: The Mesozoic Geology of Arches and Canyonlands National Parks, Kindle edition:
Luca's father, Americo Campanaro, said: "I feel like my heart has been ripped out." Mr Campanaro added: "He was a big lad, a big unit, that's why he was a goalkeeper, with a big heart to match. A gentle giant."2018 December 11, “Aylesbury goalkeeper, 14, dies after match injury”, in BBC News:
Etymology Formerly unite, a later form of unity; see unity.
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For each unit.
We have to keep our unit costs down if we want to make a profit.
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Mathematics, Sciences Having a size or magnitude of one.
Consider the following time sequence Z#95;t#61;A#92;sin(#92;omegat#43;#92;theta), where A is a random variable with a zero mean and a unit variance and #92;theta is a random variable with a uniform distribution on the interval #91;-#92;pi,#92;pi#93; independent of A.1990, William W. S. Wei, Time Series Analysis, →ISBN, page 9: