Concerning the crossing of roads ("at least three"), from latin trivialis ("crossroads"). The fact that these places have posts and places of rest for travellers made them ideal for the banal conversations among strangers, and from there comes the meaning "unimportant or uninteresting". See trivia.
It means that it has no value or interest. Little valuable. Trivial, insignificant, bland, childish, trivial, futile, frivolous. It can also mean known, trite, ordinary, regular, vulgar.
Trivial: adj. That it lacks all importance or interest.
Simple, simple, insignificant, that it lacks inportancia, superficial.