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."

Definitions of specification

n the act of naming explicitly

Type of:
the verbal act of naming

n a detailed description of design criteria for a piece of work

computer architecture
the art of assembling logical elements into a computing device; the specification of the relation between parts of a computer system
network architecture
specification of design principles (including data formats and procedures) for creating a network configuration of data processors
neural net, neural network
computer architecture in which processors are connected in a manner suggestive of connections between neurons; can learn by trial and error
Type of:
description, verbal description
a statement that represents something in words

n a restriction that is insisted upon as a condition for an agreement

Type of:
confinement, restriction
the act of keeping something within specified bounds (by force if necessary)

n (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 use of an invention

Type of:
document, papers, written document
writing that provides information (especially information of an official nature)

Sign up, it's free!

Whether you're a student, an educator, or a lifelong learner, Vocabulary.com can put you on the path to systematic vocabulary improvement.