This shipyard is the most famous boat-builder in the area, specializing in luxury yachts.

boat-builder 是由 boat（船）和 builder（建造者）组成的复合名词。boat 指"船"，builder 来自动词 build（建造）加后缀 -er 表示"建造者"。boat-builder 合起来表示"造船商"或"造船厂"。