SEC on New Jersey Transit trains stands for Secaucus and means that the train stops at Secaucus Junction.
Secaucus Junction is a rail hub where passengers can transfer between trains running to and from New York Penn Station, and services going to and from Hoboken Terminal.
New York Penn Station trains run on the upper level tracks and the Hoboken trains on the lower level. Retain your travel ticket for use to pass through fare gates when transferring between levels.
