Patanjali describes yoga
अथ योगानुशासनम् ॥१॥
atha yogānuśāsanam ||1||
“Here is the instruction in Yoga.”
योगश्चित्तवृत्तिनिरोधः ॥२॥
yogaś cittavṛtti nirodhaḥ ||2||
“Yoga is the control of the activity of the mind.”
तदा द्रष्टुः स्वरूपेऽवस्थानम् ॥३॥
tadā draṣṭuḥ svarūpe’vasthānam ||3||
“Then seer abides in itself.”
(Yoga Sutras 1-3)