Webster's Revised Unabridged Dictionary · 1913

Withers

Withers , noun, plural

[Properly, the parts which resist the pull or strain in drawing a load; from Old English wither resistance, Anglo-Saxon wiere, from wieer against; akin to German widerrist withers. See With, prep.]

The ridge between the shoulder bones of a horse, at the base of the neck. See Illust. of Horse.
Let the galled jade wince; our withers are unwrung. — Shakespeare