A synonym is an alternative name for objects such as tables, views, sequences, stored procedures, and other database objects.
SQL>create public synonym suppliers for app.suppliers;
Now, users of other schemas can reference the table called suppliers without having to prefix the table name with the schema named app..
SQL>select * from suppliers;
Drop public synonym suppliers;
SQL>drop public synonym suppliers;
This drop statement would drop the synonym called suppliers that we defined earlier.