The Sanskrit word Tantra is derived from the root ‘tan’, meaning ‘to extend.’ ‘Tra’ in Sanskrit means ‘to save’. Thus Tantra means the text that saves us by spreading our knowledge (Ajitagama I.115). The word tantrism is used in English to define all that comes under Tantra.
Tantra also means a systematic religious or philosophical system, a loom, or a science, or a technique. Tantri means a string. A tantrika is a person who knows and practices the various techniques of Tantra.
Tantra texts mention that Tantra is the guiding shastra of the present age, characterized by overall deterioration, i.e., the Kali Age.
It is said in Mahanirvana Tantra (II.8) that in Kali Yuga one should worship gods according to the procedure laid down in the Agamas. Agama is another name for the Tantra.
As described in Agama Rahasya (I-47), religious observances are governed in the earliest period called Krita Yuga or Satya Yuga by Vedas, in the next period called Treta Yuga by Smriti, in the third period called Dwapara Yuga by the Puranas, and in the present period called Kali Yuga by Agama Shastra.
One important special feature of all the aspirants of Tantra is the absence of caste discrimination and condemnation of women as inferior to men. Gautamiya Tantra text (I.7) promotes and advocate equality of all human beings.
Tantra is based on the principle that the body influences the mind and vice versa. This is known as the principle of psycho-somatic interaction. Thus, bodily acts like image worship, bhuta shuddhi, nyasa, homa, etc., are usually meant for training the mind and purifying it.
It is said in Devikalottara Agama (Verses 27 and 30) that ‘the mind running after enjoyment is unsteady like a money.’ When it is trained to be steady and still, it leads to nirvana. Hence in Tantra, importance is given to chitta shuddhi (purifying the mind).
Tantric sadhana is thus a passage from the gross to the subtle, from the superficial to the essential, and from the apparent to the real. Tantra does not look upon the world as illusory or unreal. Just as a child is taught to count, add or subtract with the help of marbles or colored objects, similarly, image worship is used in Tantra to train the mind in the art of concentration and contemplation.
A remarkable philosophical presupposition of tantric sadhana is the reconciliation of dualism and monism. Tantra argues that the world is real and plural, so long as the sadhaka is ignorant. But it becomes one when siddhi is attained through the practice of tantric sadhana.