Beginning (noun)

1. The point in time or space at which something starts.
2. The first part or stage of a process, series, or historical period.
3. A start or inception of something.
4. The origin or source of something.
5. The earliest or original state or condition.

Origin:

Middle english, from old english beginnung, from beginnan to begin.

Examples:

1. The beginning of the war marked a change in the country's history.
2. He struggled at the beginning of his career, but eventually became successful.
3. The beginning of the hike was easy, but it became more difficult as they climbed higher.
4. The company has grown significantly since its beginning.
5. At the beginning of the book, the protagonist is an innocent young man.