baseplate noun 3verb 2forms 3 noun3 •A solid piece of material that has enough strength and sturdiness to serve as the surface to which other things are attached to be supported. •The foundation of a skateboard that mounts directly to the underside of the deck using hardware. •Synonym of tie plate.Baseplates are inserted between rail and sleeper to measure the dynamic loads which are being imposed; […]. — 1964 verb2 •To fit with a baseplate. •(US) To provide (the vehicles within a fleet) with license plates registered as a batch in a particular state. formsbaseplated · baseplating · baseplates