First, dad has more than two wives ... you are the child of the first wife.

Then you usually call your father's first wife ... aunt ~

One is an ethnic group that immigrated to Taiwan Province with the National Government, commonly known as a family village where mainlanders gather. ...

Call your neighbor next door or the married old lady you know ... call your aunt ~

However, surnames are usually added in this case ... such as Aunt Zhang and Aunt Li. ...