Shipyard
A shipyard (also called a dockyard) is a place where ships are built and repaired. These can be yachts, military vessels, cruise liners or other cargo or passenger ships. Dockyards are sometimes more associated with maintenance and basing activities than shipyards, which are sometimes associated more with initial construction. The terms are routinely used interchangeably, in part because the evolution of dockyards and shipyards has often caused them to change or merge roles.
Refit
Refitting or refit of boats includes repairing, fixing, restoring, renewing, mending, and renovating an old vessel. Refitting has become one of the most important activities inside a shipyard. It offers a variety of services for an old vessel of any size and kind starting with the construction itself and what is added to it, such as hardware, electric & hydraulic systems, entertainment systems, etc.