Yōga Sūtra 2.29

यमनियमासनप्राणायामप्रत्याहारधारणाध्यानसमाधयोऽष्टावङ्गानि।

yamaniyamāsanaprāṇāyāmapratyāhāradhāraṇādhyānasamādhayō'ṣṭāvaṅgāni।

[यम नियम आसन प्राणायाम प्रत्याहार धारणा ध्यान समाधयोः अष्टौ अङ्गानि।
yama = self-restraint; niyama = rules; āsana = posture; prāṇāyāma = regulation of breath; pratyāhāra = withdrawal of senses; dhāraṇā = wearing the topic in the consciousness; dhyāna = repeatedly dwelling on the worn topic; samādhayōḥ = equilibrium state or state of flow; aṣṭau = are the eight; aṅgāni = limbs;]

Self-restraint (yama), fixed rules (niyama), posture (āsana), regulation of breath (prānāyāma), withdrawal of senses (pratyahara), wearing the topic (dharana), repeatedly dwelling on the topic (dhyana), equivalence state (samadhi) are the eight limbs.