Definitions for "Second Class"
Best rate in the US Navy. Too low to be responsible for screw-ups (that was for the first classes and chiefs to worry about), but high enough to get out of grunt work, and was normally the most technically qualified of all the rates and worked on the equipment. Known by characteristic crook of two first fingers due to constant carrying of coffee cup.
not the highest rank in a classification
accommodations on a ship or train or plane that are less expensive than first class accommodations