You could combine the attach function with limits, to display text over or under an equation
$
y=attach(limits(2x^2+7x-3), t:"term")
$
which results in the following
If you want, you can create a custom function
#let overset(a, b) = {
math.attach(math.limits(a), t: b)
}
$
overset(a(x-b)^2+c, "quadratic function")
$
