I mean, is there an antonym for first-class function?
How can I call functions that are not first-class functions?
pl.programming languages;terminology;functional programming;language design
First, the property having first-class functions is a property of a programming language, not of particular functions in it. Either your language allows for functions to be passed around and created at will, or it doesn't.Functions that accept or return other functions as arguments are called higher-order functions. (The terminology comes from logic.)  Functions that don't are called first-order functions. Perhaps this latter notion is what you wanted.