In Roman times, when you would come to a
fork in the road, there would be signs up. The signs would point to three different
cities. On each sign was a general
census report about the city the sign pointed at.
Tri = Three
Via = Ways
Information on the sign about cities. 1+1+1 = Trivia.
Today, it means a little known factoid about something not commonly known. Jeeze, isn't that ironic.