Does the operand in a convolution have a particular name?

Question

In a convolution:

$$(f*g*h)(t) = \int f(x)g(y)h(z) \delta(t-x-y-z) dxdydz$$

do the operands $f,g,h$ have a specific name, besides the general "operand"?

Answer 1

I am aware of no such word in standard usage. On the other hand, you have the verb to convolve [functions], so you would probably be understood, were you to coin convolvand or convolutand (although surely only one of these is a legitimate extrapolation). And you can call the functions convolved or convoluted: having been subject to convolution (the former probably being preferred).

Even operand is not often used. Normally you'd see something like input or argument. This case is a bit tricky, as technically convolution is a binary operation from integrable functions to integrable functions (no doubt with an associated semigroup structure on it), so the argument of $(f * g)$ could be $f$ or $g$, or the variable that $(f * g)$ is applied to as a function.