concinnity

concinnity - noun - internal harmony or fitness in the adaptation of parts to a whole or to each other; elegance, especially of the literary style.

See, I would have used this to describe one of the most beautiful forms found in creation, however it seems this word applies more to literature.

de riguer

de rigueur - adj - Required by the current fashion or custom; socially obligatory.

This term was in very common use when I was growing up in New York. I now wonder how this bit of French got started in an area mostly populated by blue collar Irish and Italians. As Nelson Muntz said, "It's one of those things we'll never know, like what's the square root of a million."