The first term denotes the captain of the ship (Revelation 18:11–17). The second refers to those who sail from port to port, that is, coasters (as opposed to open-sea navigation). The third describes those who sail the ship, while the fourth is a catch-all phrase referring to any whose daily work involves the sea. With the latter group we may also think of labourers who load and unload the ships.
17 For in a single hour all this wealth has been laid waste.”And all shipmasters and seafaring men, sailors and all whose trade is on the sea, stood far off