An upperclassman is a student in one of the last two years of an American high school or university — a junior (year three) or a senior (year four). The opposite is 'underclassman', a first-year or second-year student. This word belongs to American school life and appears constantly in American films, TV shows and campus talk, where the difference between the older and younger students matters a lot: who runs the clubs, who sits where, who is allowed to do what. British schools and universities do not use it at all; they say 'final-year student' or name the year. Two things to notice. It is not about age or ability — a slow student who has been there four years is still an upperclassman. And it is not about class in the money sense; the 'class' here means the group of students who started school in the same year, as in 'the class of 2024'. The form ends in -man, which once covered everyone, but many American schools now prefer 'upperclass student' or just 'juniors and seniors' so that it fits all students. You will still see 'upperclassman' everywhere, especially in older writing and in sports.

（美國高中或大學的）高年級生，即三、四年級學生