Outside the fields of ecology, genetics, and music, where the term has specialized definitions, to be dominant simply means that one is the most prominent member of a group or the member who exercises most influence, authority, or control where the others are concerned. To be erotically dominant is to be the partner who controls or directs at least the sexual aspects of an encounter or a relationship.
Women in our society frequently believe they have neither the right nor the ability to be dominant, while many men think they must be. Neither assumption is true, of course; but on the basis of such misunderstandings, women who prefer to be dominant in their sexual lives must often overcome fears that their erotic desires will undermine their femininity, while some men fall into power struggles with their partners, fighting for authority they do not really want in the first place, in order to show that they are masculine. In these sorts of circumstances, all partners can find themselves frustrated both erotically and relationally.
The prejudice that freights erotic dominance appears to gain legitimacy from an underlying belief that it is better to be dominant than to be submissive. That notion might be true in the wild, where the genes of a dominant animal are more likely to survive than those of a submissive one, or in competitive sports and the corporate jungle where dominance is seen as a virtue to be rewarded. The concept is also sometimes a tool of social management that denies people the right to express themselves as they wish if they do not fit conventional stereotypes. But the view is never true where people value intimacy; and intimacy, or at least the desire for intimacy, is at the heart of most human sexual relationships.
Being dominant in an erotic encounter can simply mean being the more active partner, or “running the fuck,” in Sybil Holiday’s eloquent phrase: deciding when to kiss, when and where to touch, when and in what order the clothes come off. Being the dominant partner in a relationship can be a tremendous responsibility that entails conceiving, organizing, and executing intimacy and even day-to-day activities so that all parties are fulfilled and satisfied. But the two poles of dominance and submission are actually complementary, equal partners: neither can exist alone in any sort of relationship, like the top and bottom of a box. In intimate human relationships dominant and submissive are terms of bipolar complementarity, not of hierarchy.
In the BDSM world of Bondage & Discipline, Dominance & Submission, Sadism & Masochism, dominance can be considerably more exacting than in vanilla relationships. A dominant may legitimately expect a submissive to obey her commands, respect her person, and fulfill her wishes, while accepting her domination gratefully and with grace. But apart from bad porn and masturbatory fantasies, the dominant does not always get what she wants, and the submissive exists for her pleasure only by agreement. That agreement, that the partners will pretend they are not equal, is made in part so erotic energy can easily flow back and forth between them as a conscious matter of give and take, instead of moving in only one direction. The agreement can have enormous force and may even last a lifetime, but it is unlikely to survive unless the submissive also gets what he needs to feel fulfilled.
Mutual self-awareness and respect are important if people are going to safely expose the desires that fuel their erotic lives. In order to avoid hurt feelings, resentments, contentions, and damaged relationships, it helps if all parties tell the truth; keep their agreements; and relate to each other safely, consensually, and without exploitation. Based on those behaviors people can build deep foundations of trust together, and on the basis of that trust they can build real intimacy that will allow a submissive to empower himself by serving, honoring, obeying, and otherwise empowering his dominant, while all partners can enjoy the fulfillment they fundamentally seek.
Incidentally, I’ve been calling people dominant and submissive for ease of the convention; but it is inaccurate to identify behaviors as if they were labels for human beings. Nobody is just a dominant or a submissive; these words describe traits or behaviors rather than whole human beings in relationships.