'Treenail' definitions:

Definition of 'treenail'

From: WordNet
noun
A wooden peg that is used to fasten timbers in shipbuilding; water causes the peg to swell and hold the timbers fast [syn: treenail, trenail, trunnel]

Definition of 'Treenail'

From: GCIDE
  • Treenail \Tree"nail`\, n. [Tree + nail.] (Shipbuilding) A long wooden pin used in fastening the planks of a vessel to the timbers or to each other. [Written also trenail, and trunnel.] [1913 Webster]