Yours, Etc.: Origins and Uses of 8 Sign-Offs
"arithmetic, music, geometry, astronomy," 1804 (see liberal arts), from Latin quadrivium, which meant "place where four roads meet, crossroads," from quadri- "four" (see quadri-) + via "way, road, channel, course" (see via). The adjective quadrivial is attested from late 15c. in English with the sense "having four roads."