What is the meaning of Heddle?

A component in a loom, being one of a number of similar components, through the eye of each of which a distinct strand of the warp is threaded.

One of the sets of parallel doubled threads which, with mounting, compose the harness employed to guide the warp threads to the lathe or batten in a loom.

To thread each strand of the warp through the eye of a heddle.

Source: wiktionary.org