spec vs specification

spec and specification both are nouns.

Word	Noun	Adjective	Verb	Adverb
spec	Yes	No	No	No
specification	Yes	No	No	No

As nouns, spec and specification are synonyms defined as:

spec and specification: a detailed description of design criteria for a piece of work

spec (noun)	specification (noun)
a detailed description of design criteria for a piece of work	a restriction that is insisted upon as a condition for an agreement
	a detailed description of design criteria for a piece of work
	naming explicitly
	(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