What is Master Of A Ship?

Legal Definition
Mar. law. The commander or first officer of a ship; a captain. (q. v.)

2. His rights and duties have been considered under the article Captain. Vide also, 2 Bro. Civ. Adm. Law, 133; 3 Kent, Com. 121; Wesk. Ins. 360; Park. on Ins. Index, h. t.; Com. Dig. Navigation, I 4.
-- Bouviers Law Dictionary
Legal Definition
In maritime law. The commander of a merchant vessel, who has the chief charge of her government and navigation and the command of the crew, as well as the general care and control of the vessel and cargo, as the representative and confidential agent of the owner. He is commonly called the "captain." See Martin v. Farnsworth, 33 N. Y. Super. Ct 26O; Hubbell v. Denison, 20 Wend. (N. Y.) 181.
-- Black's Law Dictionary
Legal Definition
One to whom is committed the care and management of a ship. See 33 N. Y. Super. Ct. 246.
-- Ballentine's Law Dictionary