The longer one is out to sea the more salty you become. Sea time is the only way to become salty. The idea is you are oit in the salty air so long you yourself, like your ship, become salty. A salty person develops knowledge of the ways of the seas, of his ship, and developes the necessary no b.s. attitude it takes to handle the environment
All of this is referred to as salty.
As a youngun I was once bragging about my sea time. I was put in my place when told by the other guy, " I have more time on a salt water shitter than you have in the navy. " The reference there is the navy doesnt waste fresh water on toilets, we use sea water. He had more time on the crapper than I had in service.