what are the formal names of operands of unary operations? In case of binary operations, operands have formal names.
Taking addition for example:
$$a + b$$
We can formally call $a$ the augend and $b$ the addend. Names for operands are available in individual Wikipedia articles, for addition it is here: Addition, as well as all-in-one in this page: Calculation results. Some of them are available as well in this question: What are the formal names of operands and results for basic operations?
But what I just cannot find anywhere is... Formal details regarding unary operations. My question is, do operands of unary operations have formal names? I suspect the answer is yes, but what are they?
Taking a list from Wikipedia Unary operation for C programming language for example:


*

*Increment: ++x, x++

*Decrement: −−x, x−−

*Address: &x

*Indirection: *x

*Positive: +x

*Negative: −x

*Ones' complement: ~x

*Logical negation: !x

*Sizeof: sizeof x, sizeof(type-name)

*Cast: (type-name) cast-expression
Disregarding the programming context, and considering only the operations met also in mathematics, does anyone know the names for operands in these? In case of $+1$, is $1$ the addend? In case of $-5$, is $5$ the subtrahend? What about incrementing, is the operand called... incremend?

I would suggest neo-Latinisms as these terms do not exist historically.
"Addend" and "subtrahend" are definitely wrong, since these refer to quantities which are to be added or subtracted; I might suggest "signand" in both cases instead (for the unary sign operators).
One might similarly refer to "increscend" or "decrescend" for the argument of the ++ and -- operators. In any event, they are certainly "operands" in general.
