Patanjali Yog Sutra
स्थिरसुखमासनम् ॥२-४६॥
Posture (asana) is to be seated in a position which is firm but relaxed.
english translation
शरीर की वह स्थिति जिसमें शरीर बिना हिले- डुले स्थिर व सुखपूर्वक अवस्था में रहता है । वह आसन कहलाता है ।
hindi translation
sthirasukhamAsanam ॥2-46॥
hk transliteration by Sanscript