Do you get a new chemical compound if you mix sodium hydroxide and water?
According to Oxford's dictionary of chemistry "A compound is a mixture of two or more elements in a fixed ratio".
So if $\ce{NaOH}$ (in solid state) is added to water, it just dissociates into its constituent ions that are $\ce{Na+}$ and $\ce{OH-}$. You can add any ratios of two until you cannot add any more.