Swingletree

Part of speech: noun

Definitions

1. The pivoted wooden bar on a horse-drawn vehicle's harness to which the traces are fastened so the pulling force is shared evenly
2. A horizontal crossbar at the front of a cart or plough harness that the animal's traces hook onto to distribute the load
3. The bar attached to a horse's harness that the traces connect to, allowing a carriage or plough to be pulled smoothly

Etymology: Swingletree is a plain compound: "swingle," the wooden bar or swingle that a harness hitch is fastened to, joined to "tree," a word here meaning a wooden beam or crossbar. The second element is the older sense of "tree" as a piece of timber, the same sense that survives in "whiffletree," "singletree," and the shafts or "trees" of a carriage. The word therefore describes its object by its material and its function: a swinging wooden bar. The first element carries a sense that has shifted. "Swingle" in its tool sense referred to a flail-like or beating implement, and the "swingle" of flax-processing was a wooden blade used to beat flax fibres free of woody stalk. Those meanings belong to the same family of swinging, striking motions, which is why the name fits a bar that pivots and swings between animals. Had the harness crossbar been called simply a "bar," the swinging motion that makes it useful would not have been named at all.

Synonyms: whiffletree, whippletree