To see a gavel in your dream, symbolizes justice. It may refer to a problem that you need to acknowledge and confront.
To dream that you are using a gavel, represents a resolution to a problem. Something has been decided.
To dream of a gavel, denotes you will be burdened with some unprofitable yet not unpleasant pursuit. To use one, denotes that officiousness will be shown by you toward your friends.
An ultimate or final authority or judgment. Someone banging a gavel can mean you're feeling subject to an authority other than yourself or vulnerable to others' judgments somehow in your real life. You may also have done something you could get in trouble for. Take inventory of irresponsible or dishonest things you've done and make amends (apologize or take other action to make things right).