When it comes to a very large floating structure, the possibilities are endless! From massive oil rigs to gigantic floating hotels, there are plenty of synonyms for this term. One possible synonym for a very large floating structure is a floating platform, which can be used for a variety of purposes including drilling, research, or even as a base for offshore wind turbines. Another synonym for a very large floating structure is a floating city, which can include a variety of different buildings and amenities to support a large population. Other possible synonyms include floating structures, marine structures, or even simply vessels or boats that are capable of supporting a large amount of weight.