The Latin trivium meant a "three-way junction" — from tri- ("three") and via ("road"). Roman towns were full of them, and like crossroads everywhere, they were places where strangers met, gossip was exchanged, and news travelled.
Crossroads Chatter
The adjective trivialis meant "of the crossroads" — and by extension, "common" or "ordinary," the kind of thing anyone might pick up at the corner where three roads converged. It was not initially a negative word, just a casual one. By the late Roman period, however, "trivial" carried a slight whiff of the unimportant or the merely popular.
The Three-Road Curriculum
Medieval scholars revived the word in a very different sense. The trivium in a medieval university was the first three subjects of the seven liberal arts: grammar, logic, and rhetoric. The next four — arithmetic, geometry, music, and astronomy — made up the quadrivium. Together they formed the standard arts curriculum across Europe.
Originally, "trivial" was the adjective for these three foundational subjects. They were the basics every educated person was expected to know. Over time, however, "trivial" drifted again toward its older Roman sense of "everyday" and then to "unimportant." By the 16th century, the word had detached from the curriculum and become a general adjective for the slight or insignificant.
Trivia, the Plural
The English word trivia (the noun, as in trivia night) was popularised by the Anglo-American writer Logan Pearsall Smith, who titled his books of short essays and aphorisms Trivia (1902) and More Trivia (1921). His use of the word was self-deprecating — "small things, fragments" — but it caught on. By the 1960s, "trivia" had become the standard word for obscure factual knowledge of the kind tested in pub quizzes.