Definitions
1.nounThe fifth major tone of a musical scale (five major steps above the note in question); thus G is the dominant of C, A of D, and so on.
2.nounThe triad built on the dominant tone.
3.nounA gene that is dominant.
4.nounA species or organism that is dominant.
5.noun(BDSM) The dominating partner in sadomasochistic sexual activity.