swingletree

from WordNet (r) 3.0 (2006)

swingletree
    n 1: a crossbar that is attached to the traces of a draft horse
         and to the vehicle or implement that the horse is pulling
         [syn: {whiffletree}, {whippletree}, {swingletree}]

from The Collaborative International Dictionary of English v.0.48

Swingletree \Swin"gle*tree`\, n. [So named in allusion to its
   swinging. See {Swingle}, v. i., and cf. {Swingtree}.]
   A whiffletree, or whippletree. See {Singletree}.
   [1913 Webster]

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