A polywere is one term for someone who feels they have not one, but a combination of different phenotypes or weresides.
A polywere feels that they have traits of, or share a strong connection with more than one type of nonhuman animal, often either seperately, or as a synthesis of traits of different creatures.
It is possible that there is some confusion generated in some people, by having more than one totemic influence, causing them to believe they have more than one animal side, when what they actually have is more than one guide, or because the traits they have been taught are associated with a certain animal might be traits shared or possessed by another.
An actual polywere is someone who has a were connection with more than one kind of nonhuman animal.
It is possible to be, say, a wolf, and have panther as a guide, and to have had visions or dreams of being a non-wolf animal without being a polywere.
Determining this sort of thing for ones-self is, of course, something you must do for yourself, with a lot of soul-searching. Nobody else can tell you whether your perceptions of your own identity are right for you or not.
There is some prejudice in the werecommunity that people who claim more than one phenotype are faking, or flaky, or mistaken. On occasion, it is true that while someone is making their personal journey through life, determining who and what they are, that their understanding of their identity may change over time. Often, people enter the community convinced they are a werewolf, and then later realize they are another type of creature altogether.
There are, however, longtime members of the community who, after searching inside themselves, determine that they are not one single type of creature (and what where is?), but share traits of several.
Polyweres are something different indeed. These are people who have more than one phenotype. Many believe that most people who think them self to be a polywere actually have a very strong totem that feels like a wereside. Strong totems sometimes will incorporate themselves into your essence so much so that it's easily mistakable for another wereside. Anyone can have a totem, which also leads me to believe that maybe some people who claim to be weres are actually only feeling a totem in their body, mind, and soul. Perhaps that's why some are puzzled when they don't feel "wereish" anymore or for a long period of time. Totems tend to come when you need them, and leave when their work with you is done, but some stay for life. They are similar to spirit guides, but not the same. They like to have you experience the world from their point of view. Any animal can be a totem, just like any animal can be a therian's phenotype. There are some true polyweres out there, though I think they are rarer than most people think. They may or may not know who they are.