Is a galvanic cell only called that if copper and zinc are used?
Voltaic cell and galvanic cell are both synonyms for the same thing: An electrochemical cell, which produces an external electric current. So the two terms can be used interchangeably.

Check out also a site from Georgia state University, where it says:


  Electrochemical cells which generate an electric current are called voltaic cells or galvanic cells, and common batteries consist of one or more such cells.




Addendum: Nevertheless there might be some galvanic cells, like the Daniell Cell, which have a defined electrode material and defined electrolyte concentrations to supply a specific voltage.

For the Daniell cell these would be:

$$\begin{array}{lc}
\text{Electrode material:} &amp; \ce{Zn|Zn^{2+}||Cu^{2+}|Cu}\\
\text{Electrolyte concentrations:} &amp; c(\ce{Zn^{2+}}) = c(\ce{Cu^{2+}}) = 1\ \mathrm{mol\ l^{-1}}\\
\text{Voltage:} &amp; U(25\ \mathrm{°C}) = 1.10\ \mathrm{V}
\end{array}$$