The term specification is used in multiple contexts in relation to project management. In all such contexts a specification is a document drawn up as a result of concerted effort by project management personal, sometimes including the input of any persons providing financial backing or commissioning the project in question. A requirement specification is a document that describes as completely as possible a product or service to be created, including prerequisite function, behavior, and other characteristics. A design specification defines essential performance characteristics or goal to be satisfied by the completed. A product specification is a document describing a product in a manner through which a working model of the product can be built or created. These are all documents which management personnel would make use of prior to the creation of a prototype product or model service. But a test specification is used after the creation of said product or service. It is a document written which details the necessary steps which project management must take to effectively test the product or service to ensure it meets the defined standards in both the design and product specifications. In other words the test specification describes the procedures necessary for determining whether the requirements of all the other specification documents have been satisfied.
This term is defined in the 3rd and the 4th edition of the PMBOK.