n. A person, such as a physician, who prescribes medication
the GNU version of the Collaborative International Dictionary of English
n. One who prescribes.
The Century Dictionary and Cyclopedia
n. One who prescribes; one who gives rules or directions, especially in medical treatment.
Word Usage
"The normative claim of a sovereign to be the exclusive prescriber of laws has weakened in an age of interdependence, and the power to exclusively regulate within borders has declined."