Spec vs Specification

When to use each in English, with meaning, register, and examples.

Spec

InformalBeyond 10,000 (less common)

Specification

Top 3,000 (common)C1noun
Most formal: SpecificationMost common: Specification
 SpecSpecification
Pronunciation🇬🇧 //spɛk//🇺🇸 //spɛk//🇬🇧 /["/ˌspesɪfɪˈkeɪʃn/"]/🇺🇸 /["/ˌspesɪfɪˈkeɪʃn/"]/
MeaningShort for specification, used in business and tech.A detailed description of something's features or requirements.
ExampleWe need to review the spec before starting the project.the technical specifications of the new model *(= of car)*
RegisterInformalNeutral
How commonBeyond 10,000 (less common)Top 3,000 (common)
CEFR level-C1
Part of speechnoun
Collocationsproject spec, design spec, software speccomplete, detailed, full, develop, draw up, write, according to the/​your specifications, to the/​your specifications
Antonymsgeneralize, neglectvagueness, ambiguity, generalization
Common mistakesConfused with 'specification' as a formal term., Misused in plural forms, should remain singular as 'spec'.Confused with 'specifically' — they have different uses., Using it in informal contexts where simpler words work better., Mistaking it for 'speculation' which means guessing.
Usage notesUsed mainly in technical contexts or casual conversations, but might be too informal in formal reports.Use 'specification' in formal contexts like contracts or technical documents. Avoid in casual conversations. It's more appropriate for discussions focused on details.

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Spec

Frequently asked questions: Spec vs Specification

What's the difference between Spec and Specification?

Spec: Short for specification, used in business and tech. Specification: A detailed description of something's features or requirements.

Which is more formal: Spec and Specification?

Specification is the most formal of these.

Which is more common: Spec and Specification?

Specification is the most common in everyday English.

Can you show an example of each?

Spec: We need to review the spec before starting the project. Specification: the technical specifications of the new model *(= of car)*

Can I use Spec and Specification interchangeably?

Not always. Spec and Specification are related and overlap in some contexts, but they differ in register, how common they are, and usage, so swapping one for another can change the meaning or tone. Check the differences above before substituting.

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