The leader, or dominant individual, or pair, in a pack or group of people. The alpha may be male or female, or both as a pair. This distinction comes from studies of African wild dogs and their behavior. In many cases, the female is more dominant than the male and keeps her alpha position for the remainder of her life, whereas the alpha male's position changes often. Beta males tend to compete for the alpha position, especially among large dog packs.
Women want men to be alpha when they date to ensure that a man is capable of leading a relationship. We can learn a lot for wild dogs in our dating relationships. Be an Alphadog.