युज्
Yuj
Sanskrit verbal root from which “yoga” derives. Means “to yoke”, “to join”, “to unite”.
The original image is the yoke that joins oxen for work together. Applied to yoga, it suggests the union of individual consciousness with universal consciousness, or the integration of body, mind and spirit.
This root appears in the Ṛg Veda in ritual contexts and later acquires the contemplative meaning we know today.
In the texts
In Bhagavad Gītā 2.38, Kṛṣṇa uses yujyasva — “unite yourself”, “prepare” — when instructing Arjuna: “tato yuddhāya yujyasva” (then prepare for battle). Here yuj means not just “to join” but to enter a state of integrated equanimity, where action arises without attachment to results.
The Yoga Sūtras of Patañjali systematize this union as citta-vṛtti-nirodhaḥ — the cessation of mental fluctuations. The term yoga appears in the second sūtra as the definition of the complete path.