What does it mean to dream about master?
A master in a dream often represents authority over you, a sense of being controlled or driven, or a demanding part of yourself, rather than a literal person.
Four ways to read it
Each reading below comes from a named tradition and a cited source, so you can see where it came from and decide what fits your dream.
Freud
Freud would read a master as a stern image of authority, akin to the inner father or the demanding conscience that commands and judges. He would ask what part of the self the dreamer feels ruled or driven by.
After Freud, The Interpretation of Dreams (Brill trans., 1913), public domain.Jung
Jung might see a master as a controlling figure, sometimes a shadow form of authority, the part that drives you hard or demands submission. The figure can reflect an inner tyrant as much as any outer one.
Jungian concept (our summary).Modern
A threatening or domineering figure can set off the mind's rehearsal of being controlled or overpowered, so the dream may be practicing how you would face such pressure. Notice whether the master stands for a real authority or for the demands you place on yourself.
Threat-simulation theory (our summary).Mythological
The harsh master and overlord appears across story as the figure whose rule must be served, escaped, or overthrown, from cruel kings to taskmasters of bondage. The figure tends to embody domination and the longing for release from it.
Rosmerta Publishing editorial synthesis (after Bulfinch; Brewer).