doctrine

From Middle English, borrowed from Old French, from Latin doctrina, meaning 'teaching, instruction, learning, knowledge.' That Latin word comes from doctor, 'a teacher,' rooted in the verb docere, 'to teach.'

The word has stayed close to its roots — from the general Latin idea of instruction or learning, it narrowed in English toward a specific body of teachings, especially ones held to be authoritative.

It shares its root with 'doctor,' which comes from the same Latin word for 'a teacher.'