Definitions for "carriage bolt"
Keywords:  bolt, shank, nut, round, timber
a type of bolt threaded only at the end opposite the head, used mostly for fastening pieces of timber together, and inserted into pre-drilled holes.
a round-headed bolt that can be set flush with the surface.
A bolt with a rounded head that is pulled down onto the surface of the wood as the nut is tightened. Used to hold structural members together, the rounded head gives a finished look to the bolt. Bolts should be checked annually and tightened if necessary.