The anima is the female component of the male and the animus the male component of the female. These are archetypes from the collective unconscious and refer to the bisexual nature of human beings. The opposites enable men and women to experience each other in relation to archetypal projections. Furthermore, they are archetypal traits that have to be integrated for men and women in the pathway to individuation.
Jung talks of integration in terms of appropriateness, as he offers a counter-argument that suggests inappropriate integration can lead to damaging archetypal inflation.