Second master (French: Second-maître) is a military rank used in multiple Francophone navies across the world as well as a former rating in the Royal Navy.
Second master was introduced in 1753 and indicated a deputy master on third-rate ships of the line or larger.
Second masters were paid significantly more than master's mates, £5 5s per month.
[1] A second master was generally a master's mate who had passed his examination for master and was deemed worthy of being master of a vessel.
[2] Master's mates also acted as second master of vessels too small to be allocated a warranted master.