What is that part of a prescription which contains the directions to the patient. It is usually prefaced by S or Sig. (an abbreviation for the Latin signa, imperative of signare to sign or mark) called?

signature — (Pharm.) That part of a prescription which contains the directions to the patient. It is usually prefaced by S or Sig. (an abbreviation for the Latin signa, imperative of signare to sign or mark). (Webster's 1913.)

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