To Store a Symbol
You do not have to save a symbol in order to continue using it in the drawing. However, to make symbols available for use in other drawings, you must save them to disk as .sym files. You can save any symbol in the drawing as an individual .sym file.
1. On the Annotate tab, click > 
Define Symbol. The SYM DEFINITION menu appears on Menu Manager.
Define Symbol. The SYM DEFINITION menu appears on Menu Manager.2. Click Write.
3. Specify the symbol by choosing Name or Pick Inst from the GET SYMBOL menu.
4. Type the directory path from the directory specified by pro_symbol_dir configuration option, in which to store the symbol.