operational sign; operator symbol
In computing, a symbol representing an operation, such as +, -, *, /.
This program uses '+' and '-' as operational signs.
演算子 is the more common term for 'operator' in programming contexts. 演算符号 is less frequent and may refer specifically to the written symbol rather than the abstract operator.
Compound of 演算 (operation, calculation) and 符号 (sign, symbol).