divemaster

[ dahyv-mas-ter, -mah-ster ]
/ ˈdaɪvˌmæs tər, -ˌmɑ stər /

noun

a professional qualified to oversee scuba diving operations, as in salvage work or at a resort, and responsible for procedures and safety, monitoring the whereabouts of divers underwater or at the surface, and making rescues when necessary.

Origin of divemaster