The term "peacock" is commonly used to refer to birds of both sexes. Technically, only males are peacocks. Females are peahens, and together, they are called peafowl.
Peacocks are large, colorful pheasants known for their iridescent tails. When the tail feathers spread out it boast colorful "eye" markings of blue, gold, red, and other hues. The large train is used in mating rituals and courtship displays. It can be arched into a magnificent fan that reaches across the bird's back and touches the ground on either side. Females are believed to choose their mates according to the size, color, and quality of these outrageous feather trains. Source from National Geographic