After being called "freshman" (being in the first year in high-school or college), a high-school or college student is called a "sophomore".
The description emerged at Cambridge in 1688. The word sophomore came from the Greek word sophos, meaning wise, and moros, meaning foolish.
So a second-year student is believed to be somewhere between ignorance and wisdom. Also, when we say something is "sophomoric," we mean it is pretentious or foolish.