It is probably an embarrassingly simple question, but here is the background: I find myself struggling to verbalize the conceptual, generic name for the terms in simple polynomial equations that are not directly in apposition to unknowns when doing parenting homework.
Just trying to express the very basic concept of "move all the terms with $x$-es to the LHS of the equation, and all the terms without $x$-es to the RHS."
"Constant" doesn't seem like a good choice, because the unknowns are not necessarily "random", such as in the most common one-equation/one-unknown elementary algebra problem.
I am not being picky. I just see that terminology from functions is spilling into the vocabulary of equations, creating noise in trying later to explain the concept of a "variable."