lanval Wrote:Can someone explain to me the difference between ちちおや , ちち and とうさん ? とうさん is for other people's, ちち for the own father if I remember correctly, but ちちおや ?ちちおや and ちち are often interchangeable. とうさん is a friendly word for "father" and slightly more informal than おとうさん. All these words can refer to either your own or another person's father. ちち and ちちおや are more formal than おとうさん and とうさん.
Sometimes ちち means the Father, i.e., God. Also, noun+の+ちち can have different meanings just like "father" in English. For example, バッハは音楽の父だと呼ばれている means "Bach is called the father of music." ちちおや and other synonyms don't have this kind of usage.