To the practitioners of Tantra, the term refers to a shakti, a human female participant in the maithuna, or sexual rites; or even to the parched grain as one of the five ingredients used in the panca-tattva rite because of its physical resemblance to the yoni, the female genitalia.
Shaktis are called "mudras" because in the process of ritualistic and yogic coitus they have an effect similar to body and hand mudras. Mudras awaken dormant psycho-physical centers and purifies certain subtle channels allowing for the circulation of energies to take place; Mudras facilitates concentration, and are a powerful means of communing with the forces and divinities lying within man's inner nature; women have a great access to psychic energies; thus, the sexual yogic act, when properly conducted, does the same thing. Being highly respected, a woman proficient in the Tantric arts is referred to as a "mudra," or to be more specific, "Karma mudra," of which there are five kinds, categorized according to various psycho-physical characteristics.
In another sense, "closed electrical-circuits" of the subtle channels in the physical and etheric bodies are also known as "seals," or mudras.
In passing, we should mention that the large earrings worn by members of the Nathaa Order in India are likewise called "mudra."
The Kagyu sect of Vajrayana Buddhism uses the suffix "maha" meaning "great" in association with the term "mudra." Thus, the conjoined word mahamudra means "the Great Seal," or "the Great Symbol." In this context, the word refers to a state of direct realization and experience of the ultimate nature of the Mind or Reality where all dualities and sense of separateness from All that Is are transcended.
Putting aside complexities, the definition of mudra is simply "symbolic gesture."
Chogyam Trungpa in his book, "Mudra," defines the word as,
"a symbol in the wider sense of gesture or action. It is the inspiring color of phenomena. Also it is a symbol expressed with the hands to state for oneself and others the quality of different moments of meditation, such as touching the earth with the right hand as a witness to Buddha's freedom from emotional and mental frivolousness."
Yoga teachings in general explain that mudras denote the hand gestures and movements used in the performance of dances, rituals, rites, and while engaging in spiritual exercises such as meditation. Mudras symbolically express inner feelings and inner psychological states; they also generate various qualities such as fearlessness, power, charity, and peace in the practitioner and to on-lookers.
In another ancient text called Soma-Shambhu-Paddhati, a great number of these hand mudras are described. Perhaps the best known by yogic practitioners and students are abhaya-mudra, anjali-mudra, cin-mudra, dhyana-mudra, and jnana-mudra. Some of these mudras are known by other names, especially in other cultures and spiritual traditions.
It is this latter understanding of mudra that we shall be dealing with in this series of articles. To sum up, we present Nik Douglas' definition of "mudra" to be found in the glossary of his book, Sexual Secrets :