The title on this post says it all. This week I learned there is actually a name, "matchfix", for an operator that is called like a function. To put this in its familiar context, here's a summary of the ways a two-argument operator can be called:
- op arg1 arg2
- arg1 arg2 op (also known as Reverse Polish Notation)
- arg1 op arg2
For reference, see the Google search 'matchfix -cricket -horse'.
It looks like the origins of "matchfix" may come from MACSYMA, the computer algebra system.
Now if the language you're designing or describing has a way to invoke operators like ordinary function calls, you know the term.