Specification

n. act of specifying; item or detail included in a description of requirements or plans; detailed written description of an invention submitted in a patent request

A specification is an explicit set of requirements to be satisfied by a material, product, or service. (ASTM definition)
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Noun
1. a detailed description of design criteria for a piece of work
(synonym) spec
(hypernym) description, verbal description
(hyponym) computer architecture
(derivation) stipulate, qualify, condition, specify
2. naming explicitly
(hypernym) naming
(derivation) assign, specify, set apart
3. (patent law) a document drawn up by the applicant for a patent of invention that provides an explicit and detailed description of the nature and usse of an invention
(hypernym) document, written document, papers
(classification) law, jurisprudence
4. a restriction that is insisted upon as a condition for an agreement
(synonym) stipulation
(hypernym) restriction
(derivation) stipulate, qualify, condition, specify

n. specification, act of specifying; item or detail included in a description of requirements or plans; detailed written description of an invention submitted in a patent request; marking (Computers)

(n.)
The designation of particulars; particular mention; as, the specification of a charge against an officer.
  

(n.)
The act of specifying or determining by a mark or limit; notation of limits.
  

(n.)
A written statement containing a minute description or enumeration of particulars, as of charges against a public officer, the terms of a contract, the description of an invention, as in a patent; also, a single article, item, or particular, an allegation of a specific act, as in a charge of official misconduct.