prescription

prescription A physician’s order for the preparation and administration of a drug or device for a patient. A prescription has several parts, including the superscription, or heading, with the symbol R or Rx, which stands for the word “recipe” (Latin for “to take”); the inscription, which contains the names and quantities of the ingredients; the subscription, or directions for compounding the drug; and the signature, often preceded by the sign s., which stands for “signa” (Latin for “mark”), giving the directions to be marked on the container. See also Appendix A, “Prescription Abbreviations.”