The short answer to this is no. There is no rule on what designers call their garments. In many cases garments with different names actually refer to the same product. Such is the case in the swim parka and swim robe category.
For the most part, traditional swim parkas are made from synthetic fabrics designed to trap heat which they do well. But these types of garments don’t breathe particularly well and they certainly don’t absorb water. A traditional swim parka may be suitable for you if you are wearing it before a race or event, when you start dry and want to stay warm up until you slip it off and get into the water. They will perform this function well. But they tend to be large and bulky and not particularly flattering, and they can not be slipped straight on after exiting the water as their polyester fleece lining is non-absorbent.
Being 100% cotton towelling with thirsty cotton loops, our towelling swim parkas are highly absorbent. We think they are perfect for swim teams and clubs, especially as an all in one garment for training and events. 100% Cotton swim parkas and robes are also simple to launder.