What is the difference between Defamation and Slanderous Acts? What are the penalties?

It was a strange experienced. I am already married and I was accused of my Ex-boyfriend's wife of having an affair with him since we are in the same office. She got wild and made some allegations without proof of truth. She then uttered words that dishonor and discredit my profession. Can I file a formal complaint against her? I am confuse.