Yoga Sutras of Patanjali · 2.54

स्वविषयासंप्रयोगे चित्तस्य स्वरूपानुकार इवेन्द्रियाणां प्रत्याहारः ॥५४॥

sva-viṣayāsaṁprayoge cittasya svarūpānukāra ivendriyāṇāṁ pratyāhāraḥ

When the senses disengage from their own objects and follow the nature of the mind itself, that is pratyahara.

— Yoga Sutras of Patanjali 2.54

Source: Sanskrit attributed to Patanjali (c. 2nd century BCE – 4th century CE). Public-domain English readings drawn from Swami Vivekananda's 'Raja Yoga' (1896) and Charles Johnston's 'The Yoga Sutras of Patanjali' (1912).