Dictionary.net

Formerly, in the British service, a gunner or a gunner's mate; one of the soldiers in a train of artillery, who assisted the gunners in loading, firing, and sponging the guns.

Formerly, in the British service, a gunner or a gunner's mate; one of the soldiers in a train of artillery, who assisted the gunners in loading, firing, and sponging the guns.

ma-tros', n. formerly a soldier set to help the gunners in an artillery train. [Dut. matroos--Fr. matelot, a sailor.]