Yab-yum (Tibetan literally, "father-mother") is a common symbol in the Buddhist art of India, Bhutan, Nepal, and Tibet. It represents the primordial union of wisdom and compassion, depicted as a male deity in sexual union with his female consort. The male figure represents compassion and skillful means, while the female partner represents insight.
The symbolism is associated with Anuttarayoga tantra and, while there are various interpretations of the symbolism in twilight language, the male figure is usually linked to compassion (karuṇā) and skillful means (upāya-kauśalya), while the female partner to "insight" (prajñā).
Yab-yum is generally understood to represent the primordial (or mystical) union of wisdom and compassion. In Buddhism the masculine form is active, representing the compassion and skillful means (upaya ) that have to be developed in order to reach enlightenment. The feminine form is passive and represents wisdom (prajna), which is also necessary to enlightenment. United, the figures symbolize the union necessary to overcome the veils of Maya, the false duality of object and subject.
In Tibetan Buddhism, the same ideas are to be found concerning the bell and the dorje, which, like the yab-yum, symbolize the dualism that must be exceeded. The sacred Tantric practice leads to rapid development of mind by using the experience of bliss, non-duality, and ecstasy while in communion with one's consort.
In Hinduism the yab-yum has a slightly different meaning. There, the embraced posture represents the divine strength of creation. The Hindu concept is the one of a passive masculine deity embracing his spouse called shakti, which represents his activity or power. The iconic yab-yum of Chakrasamvara-Vajravarahi is directly influenced from the Hinduist depiction of Kali and Bhairava in union.
The symbolism of union and sexual polarity is a central teaching in Tantric Buddhism, especially in Tibet. The union is realised by the practitioner as a mystical experience within one's own body.
As a tantric practice, Yab-yum is akin to the Karmamudrā or "actionseal". This is the tantric yoga involving a physical partner. However, the aim of the practice is to control one's winds. This sadhana is part of the completion stage.