A Dominant is a sexual participant who takes on a leadership role and consensually controls a submissive participant. This type of partnership is often referred to in the BDSM community as a D/S partnership.
A male dominant is often called a Dom, for short, or a master. A female dominant is commonly referred to as a Domme or Mistress, although the language can be altered in fun and “unconventional” ways. Their submissive partner is often called a sub for short. The word Dom is usually capitalized while sub is written in lower-case, to emphasize the power dynamic.
A Dominant may be a sex worker who serves a number of paying subs or someone who takes a dominant role in their intimate relationships. They may only dominate sexually or be dominant in all facets of their relationships, in ways the sub must continually consent to. For example, a Dominant might set rules for how the submissive should behave socially or control the submissive’s finances.
It’s important to note that Dom is short for dominant, not domineering. While these words are similar, the control dominant and domineering people exert is different. Domineering people simply control for the sake of controlling someone else. This can be very dangerous, both emotionally and psychologically, for a submissive. In contrast, a dominant person controls for the betterment and benefit of their submissive and always has their welfare at heart.