What does NaZnO2 mean ?

Dear student 
Solution to your asked query is provided below:

The formula of sodium zincate is Na₂ZnO₃​.

Sodium zincate is a salt formed by the reaction of ZnCl₂ (an acid ) with NaOH ( base) .

Reaction of Zinc metal with sodium hydroxide is given below :

Zn  + 2 NaOH ------> Na₂​ZnO₂ + H₂

Hope this information clears your doubt.
Regards