Whippletree

• (n.) The pivoted or swinging bar to which the traces, or tugs, of a harness are fastened, and by which a carriage, a plow, or other implement or vehicle, is drawn; a whiffletree; a swingletree; a singletree. See Singletree. • (n.) The cornel tree.
Found on http://thinkexist.com/dictionary/meaning/whippletree/

whippletree

1. The pivoted or swinging bar to which the traces, or tugs, of a harness are fastened, and by which a carriage, a plow, or other implement or vehicle, is drawn; a whiffletree; a swingletree; a singletree. See Singletree. '[People] cut their own whippletree in the woodlot.' (Emerson) ... 2. <botany> The cornel tree. ... See: Whip, and cf. Whi...
Found on http://www.encyclo.co.uk/local/20973

Whippletree

[mechanism] A whippletree or whiffletree is a mechanism to distribute force evenly through linkages. The mechanism may also be referred to as an equalizer, leader bar or double tree. It consists of a bar pivoted at or near the centre, with force applied from one direction to the pivot, and from the other direction to the tips. Several whipp...
Found on http://en.wikipedia.org/wiki/Whippletree_(mechanism)

Whippletree

Whip'ple·tree` noun [ See Whip , and confer Whiffletree .] 1. The pivoted or swinging bar to which the traces, or tugs, of a harness are fastened, and by which a carriage, a plow, or other implement or vehicle, is drawn; a whiffletree; a swingletree; a singletree. See Singletre...
Found on http://www.encyclo.co.uk/webster/W/31

whippletree

crosspiece of a carriage to which harnesses attached
Found on http://phrontistery.info/w.html
No exact match found