swingletree Meaning, Definition & Usage

  1. noun a crossbar that is attached to the traces of a draft horse and to the vehicle or implement that the horse is pulling
    whiffletree; whippletree.

WordNet

Swin"gle*tree` noun
Etymology
So named in allusion to its swinging. See Swingle, v. i., and cf. Swingtree.
Definitions
  1. A whiffletree, or whippletree. See Singletree.

Webster 1913