A deficiency is generally a lack of something. It may also refer to:
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deficient number
In number theory, a deficient number or defective number is a number ''n'' for which the sum of divisors of ''n'' is less than 2''n''. Equivalently, it is a number for which the sum of proper divisors (or aliquot sum) is less than ''n''. For ex ...
, in mathematics, a number ''n'' for which ''σ''(''n'') < 2''n''
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Angular deficiency, in geometry, the difference between a sum of angles and the corresponding sum in a Euclidean plane
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Deficiency (graph theory)
Deficiency is a concept in graph theory that is used to refine various theorems related to perfect matching in graphs, such as Hall's marriage theorem. This was first studied by Øystein Ore. A related property is surplus.
Definition of deficien ...
, a property describing how far a given graph is from having a perfect matching
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Deficiency (medicine), including various types of malnutrition, as well as genetic diseases caused by deficiencies of endogenously produced proteins
*A deficiency in
construction
Construction is a general term meaning the art and science to form Physical object, objects, systems, or organizations,"Construction" def. 1.a. 1.b. and 1.c. ''Oxford English Dictionary'' Second Edition on CD-ROM (v. 4.0) Oxford University Pr ...
, an item, or condition that is considered sub-standard, or below minimum expectations
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Genetic deletion
In genetics, a deletion (also called gene deletion, deficiency, or deletion mutation) (sign: Δ) is a mutation (a genetic aberration) in which a part of a chromosome or a sequence of DNA is left out during DNA replication. Any number of nucleoti ...
, in genetics, also called a deficiency
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deficiency judgment A deficiency judgment is an unsecured money judgment against a borrower whose mortgage foreclosure sale did not produce sufficient funds to pay the underlying promissory note, or loan, in full. The availability of a deficiency judgment depends o ...
, in the law of real estate
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tax deficiency
A tax is a compulsory financial charge or some other type of levy imposed on a taxpayer (an individual or legal entity) by a governmental organization in order to fund government spending and various public expenditures (regional, local, or n ...
, an amount owed in taxes over and above what has been submitted in payment
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