SUTRA: Dictionary Entry and Meaning

Webster's 1913 Dictionary Definition:
 
\Su"tra\, n.; pl. {Sutras}. [Skr. s?tra a thread, a string
of rules; an aphorism; fr. siv to sew.]

1.
(a) A precept; an aphorism; a brief rule.
(b) A collection of such aphorisms.

2. pl. A body of Hindoo literature containing aphorisms on
grammar, meter, law, and philosophy, and forming a
connecting link between the Vedic and later Sanscrit
literature. --Balfour (Cyc. of India).

 

from HyperDictionary.com

yoga sutras