Teaching (noun)

1. The profession or work of a teacher.
2. The imparting of knowledge or skills.
3. The activities of a teacher, including lecturing, giving instruction, and setting and marking work.
4. An instance of giving a lesson or instruction.
5. A body of knowledge or skills that is taught.

Origin:

Middle english: from old english tǣcing, of germanic origin; related to dutch tijding and german unterricht, from an indo-european root shared by greek deiknunai "show", deiknumi "point out".

Examples:

1. He chose teaching as a career.
2. The teaching of mathematics was difficult.
3. He was giving a teaching on history.
4. The teaching was well received.
5. The teaching of programming languages.