Nautical Term: Main mast

Definition of Main mast

The main mast is the primary vertical mast located at the centerline of a vessel. It supports the upper rigging and carries the uppermost sail, which is typically the largest sail on the vessel. For example, a tall ship may have a main mast that is over 100 feet tall and carries a royal sail or topsail that can stretch over 150 feet.

Explore other nautical terms:

Head back to the Nautical Dictionary

Take a Tour With Us!

Recommended Reading