ˌsecond-ˈclass BrE AmE adjective [only before noun]
1 . PEOPLE considered to be less important and less valuable than other people:
Why should old people be treated like second-class citizens?
2 . LOWER STANDARD of a lower standard or quality than the best:
We will not accept a second-class education for our children.
3 . TRAVEL second-class ticket/fare/compartment/cabin etc tickets etc that are for cheaper, less comfortable seats on a train or ship
4 . MAIL second-class mail/post/stamp etc relating to the system of delivering mail in Britain that is cheaper and slower
5 . UNIVERSITY DEGREE used to describe a university degree in Britain that is good, but not the highest level:
a second-class honours degree
⇨ ↑ first class (3)
—second class adverb :
He was travelling second class.