I remember myself on my first year of CS, set theory classes, at the whiteboard, trying to make a proof, but there something I was not able to prove at all, so I said 'it's trivial' and the doctor said 'yeah, it's trivial' and we went further.
The one I've always flown with is, trivial means (1) a special case of a more general theory (2) which flattens many of the extra frills and considerations of the general theory and (3) is intuitively clear ("easy") to appreciate and compute.
From this perspective, everything is trivial from the relative perspective of a god. I know of no absolute definition of trivial.
No, this was really something trivial, in the sense that you could feel it's true. Like 2+2=4 but to prove it you need to create a set of functions, axiom and a theorem
