perfect, bisexual
imperfect, unisexual

Referring to a flower, bisexual or perfect means a flower with functional* stamens and pistils.

Unisexual or imperfect refers to a flower that lacks either a functional stamen or a functional pistil (i.e., has only one type of functional sexual organ).

*Some flowers may present both male and female sexual organs, but only one type is actually functional. In such cases the non-functional organs are usually reduced in nature compared to flowers in which they are functional. See for example, male and female flowers of Ilex verticillata.