prescription

(noun) directions prescribed beforehand; the action of prescribing authoritative rules or directions. Example: "I tried to follow her prescription for success."

(noun) a drug that is available only with written instructions from a doctor or dentist to a pharmacist. Synonyms: prescription drug, prescription medicine, ethical drug. Example: "He told the doctor that he had been taking his prescription regularly."

(noun) written instructions for an optician on the lenses for a given person.

(noun) written instructions from a physician or dentist to a druggist concerning the form and dosage of a drug to be issued to a given patient.

(adj) available only with a doctor's written prescription. Synonyms: prescription(prenominal) (vs. nonprescription). Example: "A prescription drug."