Sutra

Sūtra

... ultimately deriving from PIE *siH-/syuH- 'to sew'), as does the medical term "suture." The word "sutra" was very likely meant to apply quite literally to these texts, as they were written down ... In ancient Indian literature, sutra denotes a distinct type of literary composition, based on short aphoristic statements, generally using various technical terms ... commentaries (Sanskrit bhāṣya) on the sutras were added, to clarify and explain them ...