(aviation) A dangerous condition where the mast of a helicopter contacts adjacent fixed structure while rotating, damaging the mast and potentially resulting in the separation of the main rotor from the helicopter.

(nautical) Having ten masts.

(nautical) Having sixteen masts.

(nautical) Having fourteen masts.

(nautical) Having fifteen masts.

(nautical) Having twelve masts.

(nautical) Having four masts.

(nautical) Having two masts.

(nautical) Having one mast.

(nautical) Having two masts.