A math teacher at your school is an example of an instructor.
In1867-1869he was an instructor in the U.S. Naval Academy.
In 1794 a nautical school was founded at Lima, with Andres Baleato as instructor and Pedro Alvarez as teacher of the use of instruments.
Age is no better, hardly so well, qualified for an instructor as youth, for it has not profited so much as it has lost.
On returning to Prussia he became mathematical instructor at the school of military engineering, leaving this post in 1792 to take part as a general staff officer in the war against France.