elementary set theory – Conceptual doubt in reading the domain of a relation

I can already see the heavy downvotes but any help will be appreciated.

Let there be a relation R and the domain of R is given by $$R={x:(x,y)epsilon R}$$

How should I convey this set if I am to read it out to someone?

My try was :”the set of all x such that x comma y belongs to R”

Is this right it does not make alot of sense to me .

Thanks alot in advance.