Tether \Teth"er\, n. [Formerly tedder, OE. tedir; akin to LG. tider, tier, Icel. tj[=o]?r, Dan. t["o]ir. [root]64.]

A long rope or chain by which an animal is fastened, as to a stake, so that it can range or feed only within certain limits.

Source: Webster's Revised Unabridged Dictionary (1913)
 

Tether \Teth"er\, v. t. [imp. & p. p. Tethered; p. pr. & vb. n. Tethering.]

To confine, as an animal, with a long rope or chain, as for feeding within certain limits.

And by a slender cord was tethered to a stone. --Wordsworth.

Source: Webster's Revised Unabridged Dictionary (1913)