The term yoga is a common word in the Sanskrit language, which is the language in which most of the Yoga scriptures are written. It also happens to be one of the most versatile Sanskrit terms, having a whole range of meanings that extend from simple "union" to "team," "constellation," and "conjunction." It is derived from the verbal root yuj, meaning "to harness, yoke, prepare, equip, and fasten."
The male practitioner of Yoga is referred to as a yogin or yogi and the female practitioner as a yogini. Common synonyms are yoga-vid meaning "knower of Yoga" and yukta meaning "yoked one". Sometimes the word yoga-yuj, meaning "one who is yoked in Yoga" is used. A master of Yoga may be referred to as a yoga raj ("king of Yoga") or yogendra (from yoga and indra, meaning "lord").
The term yoga is closely related to a number of words in various Indo-European languages, including the English yoke, the German Joch, and the Latin iugum, which all have the same meaning. In a spiritual context, the word yoga can have two primary meanings. It can stand for either "union" or "discipline." In most cases, both connotations are present when the term yoga is applied. Therefore, dhyana-yoga is the unitive discipline of meditation; samnyasa-yoga is theunitive discipline of renunciation; karma-yoga is the unitive discipline of self-transcending action; kriya-yoga is the unitive discipline of ritual; bhakti-yoga is the unitive discipline of love and devotion to the Divine, and so on.
What does the term unitive mean? It describes Yoga's disciplined approach to simplifying one's consciousness and energy to the level where we no longer experience any inner conflict and are able to live in harmony with the universe. In addition, unitive specifically refers to the goal of many branches and schools of Yoga, which is to realize our essential nature, the Self (atman, purusha), by consciously uniting with it. This understanding of Yoga is characteristic of those teachings that subscribe to a nondualist metaphysics according to which the Self is the ultimate singular Reality underlying all events.