Consider this script:

CREATE TABLE t (i int);
INSERT INTO t VALUES (1);
CREATE SYNONYM s FOR t;
SELECT * FROM s;
DROP SYNONYM s;
SELECT * FROM s;

It works until the end, without error. The synonym S is still available right after dropping. I cannot drop it again, though:

DROP SYNONYM s;

This results in:

SQL Error [42102] [42S02]: Table "S" not found; SQL statement:
DROP synonym s [42102-232]

And now, as expected, I also cannot use it in the query anymore:

SELECT * FROM s;