What keyword in C++ typically signifies the start of a function definition?

The keyword that typically signifies the start of a function definition in C++ is "void" when it indicates that the function does not return a value. In a function definition, the return type precedes the function name, and "void" is one of the possible return types that can be used. This keyword communicates to the compiler that the function will not return any data to the caller.

For instance, in the function declaration void myFunction(), the keyword "void" specifies that myFunction does not return a value. Conversely, if a function has a return type such as int or double, it can return corresponding data types. However, "void" is widely used for functions that perform actions without needing to return a value, making it an essential keyword in C++ function definitions.

The other options do not signify the start of a function definition. "define" is not a keyword in standard C++ for function declarations. "function" is not used in C++, as the language does not have a specific keyword for declaring functions. "main" is a special function in C++ that serves as the entry point of the program but is not a general keyword to define any function.