Magistral

1. (a.) Pertaining to a master; magisterial; authoritative; dogmatic.
2. (a.) Commanded or prescribed by a magister, esp. by a doctor; hence, effectual; sovereign; as, a magistral sirup.
3. (a.) Formulated extemporaneously, or for a special case; -- opposed to officinal, and said of prescriptions and medicines.
4. (n.) A sovereign medicine or remedy.
5. (n.) A magistral line.
6. (n.) Powdered copper pyrites used in the amalgamation of ores of silver, as at the Spanish mines of Mexico and South America.