Metacenter, in naval architecture, refers to a point of virtual intersection of the buoyancy and the vertical axis of the ship. While this term is commonly used in the field of naval architecture, there are several other terms that can be used to describe the same concept. One such synonym might be the "center of buoyancy," which is the point where the force of buoyancy acts, similar to the metacenter. Another synonym could be the "center of flotation," referring to the point where the underwater hull surface meets the waterline. Generally, these terms are interchangeable and used interchangeably depending on the context.