adjective 1 : of little or no consequence : trifling, inconsequential 2 : having no force : inoperative
In Latin, nugae are trifles—that is, things of little value, substance, or importance. In English, such things can be described as nugatory, as in "I'm not going to concern myself with such nugatory matters as obscure words from extinct languages."
Whatever its origin, nugatory has, we think, a pleasantly dismissive sound to it. And if you like the adjective, we have some nouns for you to consider as well: nugacity, which refers to something frivolous or trivial, or to triviality itself; and the obsolete (but otherwise perfectly good) nugation, meaning "the act or an instance of trifling." (Trifling is, of course, treating or dealing with someone or something in a way that shows a lack of respect or seriousness.)