Samyama is defined in the Yoga Sutras of Patanjali verses 3.1 through 3.6 as follows where the Sanskrit in Devanagari and IAST were sourced from http://alanlittle.org/yoga/patanjali.html#III and the English from B.K.S. Iyengar (1993: pp. 178–183):[2]
देशबन्धश्चित्तस्य धारणा ॥ १॥
deśabandhaścittasya dhāraṇā .. 1..
Fixing the consciousness on one point or region is concentration (dhāraṇā).
तत्र प्रत्ययैकतानता ध्यानम् ॥ २॥
tatra pratyayaikatānatā dhyānam .. 2..
A steady, continuous flow of attention directed towards the same point or region is meditation (dhyāna).
तद् एवार्थमात्रनिर्भासं स्वरूपशून्यम् इव समाधिः ॥ ३॥
tad evārthamātranirbhāsaṃ svarūpaśūnyam iva samādhiḥ .. 3..
When the object of meditation engulfs the meditator, appearing as the subject, self-awareness is lost. This is samādhi.
त्रयम् एकत्र संयमः ॥ ४॥
trayam ekatra saṃyamaḥ .. 4..
These three together [dhāraṇā, dhyāna and samādhi] constitute integration or saṃyama.
तज्जयात् प्रज्ञालोकः ॥ ५॥
tajjayāt prajñālokaḥ .. 5..
From mastery of saṃyama comes the light of awareness and insight.
तस्य भूमिषु विनियोगः ॥ ६॥
tasya bhūmiṣu viniyogaḥ .. 6..
Saṃyama may be applied in various spheres to derive its usefulness.
