To go on board a ship, aircraft, or other vehicle as a passenger. The passengers began to embark on the cruise ship for their journey across the Atlantic.
To begin a course of action, especially one that is important or demanding. She decided to embark on a new career path after years in the same industry.
To put or take (passengers, troops, or cargo) on board a ship, aircraft, or other vehicle. The logistics team embarked the supplies onto the transport plane.