The difference between Prescription and Prescriptivism

Prescription as a noun (legal):

The act of prescribing a rule, law, etc.. Also called extinctive prescription or liberative prescription. A time period within which a right must be exercised, otherwise it will be extinguished. Also called acquisitive prescription. A time period after which a person who has, in the role of an owner, uninterruptedly, peacefully, and publicly possessed another's property acquires the property. The described process is known as acquisition by prescription and adverse possession.

Prescription as a noun (medicine, pharmacy):

A written order, as by a physician or nurse practitioner, for the administration of a medicine or other intervention. See also scrip.

Prescription as a noun (medicine):

The prescription medicine or intervention so prescribed.

Prescription as a noun (ophthalmology):

The formal description of the lens geometry needed for spectacles, etc..

Prescription as a noun (linguistics):

The act or practice of laying down norms of language usage, as opposed to description, i.e. recording and describing actual usage.

Prescription as a noun (linguistics):

An instance of a prescriptive pronouncement.

Prescription as a noun:

A plan or procedure to obtain a given end result; a recipe.

Prescription as an adjective:

only available with a physician or nurse practitioner's written prescription

Prescriptivism as a noun (linguistics):

The practice of prescribing idealistic norms, as opposed to describing realistic forms, of linguistic usage.