specification

American  

[spes-uh-fi-key-shuhn] / ˌspɛs ə fɪˈkeɪ ʃən /

noun

1. the act of specifying.

2. Usually specifications.

   1. a detailed description or assessment of requirements, dimensions, materials, etc., as of a proposed building, machine, bridge, etc.

   2. Computers. a detailed description of the hardware installed, including the memory capacity, processor speed, and graphics card model.

3. a particular item, aspect, calculation, etc., in such a description.

4. something specified, as in a bill of particulars; a specified particular, item, or article.

   Synonyms:

   qualification, condition, requirement

5. an act of making specific.

6. the state of having a specific character.

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specification British  

/ ˌspɛsɪfɪˈkeɪʃən /

noun

1. the act or an instance of specifying

2. (in patent law) a written statement accompanying an application for a patent that describes the nature of an invention

3. a detailed description of the criteria for the constituents, construction, appearance, performance, etc, of a material, apparatus, etc, or of the standard of workmanship required in its manufacture

4. an item, detail, etc, specified

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Other Word Forms

• nonspecification noun
• prespecification noun
• respecification noun
• superspecification noun

Etymology

Origin of specification

First recorded in 1605–15; from Medieval Latin specificātiōn- (stem of specificātiō ), equivalent to specificāt(us) (past participle of specificāre “to mention, describe”; specific, -ate ¹ ) + -iōn- -ion

Explanation

We sometimes call them "specs," but a specification has no relationship to eyeglasses! Instead, it is an explicit detail of a design, presenting the exact way something specific must be constructed. For example, blueprints contain the specifications for a building. In the 17th century, the word specification emerged with the meaning of giving something a specific quality. The technical meaning, applied to building and engineering plans, developed in the late 18th century. The meaning of the word is precise, referring to specific plans, although just because it's a specification doesn't mean it is accurate. Science-fiction writer Robert Heinlein once had his character Lazarus Long make the comment, "An elephant is a mouse built to government specifications."

Example Sentences

The Black Badge specification features a dark-anodized grille and hood figurine in the place of chrome brightwork—younger, fresher, more nocturnal, but also nicely understated, which I like.

From The Wall Street Journal • Apr. 4, 2026

F1 rules dictate that manufacturers must supply engines of exactly the same specification to all their teams - works or customer.

From BBC • Mar. 10, 2026

The job specification describes the role as one of "the most important, high-profile public posts in the UK".

From Barron's • Nov. 24, 2025

He said the missile's vertical and horizontal manoevreing were tested and were found to be up to specification, according to Russia's Tass news agency.

From BBC • Oct. 26, 2025

Having absorbed Lawrence’s confidence that further efficiencies eventually would be achieved, Groves reduced the specification for Y-12 to five hundred tanks, or five racetracks.

From "Big Science" by Michael Hiltzik

Related Words

• blueprint
• spec
• stipulation