TITLE: Is there a name for the property of a function f such that $f(x,y)=f(y,x)$?
QUESTION [5 upvotes]: As in the title: is there a name for the property of a function such that $f(x,y)=f(y,x)$. 
I don't know how to be clearer than that. I tried to look for symmetric property on Google, but without any luck. Thank you!

REPLY [9 votes]: A function such that $f(x,y) =  f(y, x)$ is called a symmetric function.