The Collaborative International Dictionary
Splinter bar
Splinter \Splin"ter\, n. [See Splinter, v., or Splint, n.] A thin piece split or rent off lengthwise, as from wood, bone, or other solid substance; a thin piece; a sliver; as, splinters of a ship's mast rent off by a shot. Splinter bar.
A crossbar in a coach, which supports the springs.
The bar to which the traces are attached; a roller bolt; a whiffletree.
Wiktionary
splinter bar
n. 1 A crossbar in a coach, which supports the springs. 2 The bar to which the traces are attached; a roller bolt; a whiffletree.