We find our Catechetical Leader teaching a high school class on basic church doctrine.
Catechesist: "Class, what is the teaching office of the Church called?"
Student: "The Magic-Steering-Committee!"
Here are two links to some info on what the Magisterium is. Link1. Link2.
The word 'magesterium' comes from the Latin 'magister' which means 'teacher', 'administrate," or 'master.' A more modern form of the word comes in the form can be seen in the phrase 'governmental magistrate'. I don't remember my Latin as well as I once did, but I believe the case is genitive, which would make the word possessive. If I am correct in my cases a more literal translation might be "The Body's Teacher". Hmmm... the Body. The body of Christ. The Church. The Church's Teacher. Granted the ultimate teacher of the Church is Christ and the Holy Spirit; however, thankfully God left His church some earthly teachers to help discern the movements of the Spirit.