Yab-yum (Tibetan literally, "father-mother") is a common symbol in the Buddhist art of India, Bhutan, Nepal, and Tibet representing the male deity in sexual union with his female consort. Often the male deity is sitting in lotus position while his consort is sitting in his lap.
The symbolism is associated with Anuttarayoga tantra and, while there are various interpretations of the symbolism in the 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.
As a tantric practice, Yab-yum is akin to the Kāmamudrā or "loveseal" (sometimes Karmamudrā or "actionseal") (T:las kyi phyag rgya). This is the tantric yoga involving a physical partner. However, the aim of the practice is to control one's sexual energy, and the most advanced forms of Yab-yum practice are done mentally, without using a physical partner. Like all other yogas, it cannot be practiced without the basis of the inner heat yoga, tummo, of which kāmamudrā is an extension. This sadhana is subsumed within the Six Yogas. The iconography of Yab-yum and the maitrī practice of Kāmamudrā engenders cognition of the upaya doctrine of interpenetration.