— adj

1. matters or things that are very unimportant, inconsequential,
or nonessential; ; petty or frivolous; trivialities.
2. ordinary or commonplace; trite: trifles; trivial conversation
3. maths (of the solutions of a set of homogeneous equations)
having zero values for all the variables
4. biology denoting the specific name of an organism in binomial
5. biology, chem denoting the popular name of an organism or
substance, as opposed to the scientific one
6. of or relating to the trivium

[from Latin triviālis belonging to the public streets, common, from
trivium crossroads, junction of three roads, from tri- + via road]