Once, Twice or Thrice Removed?

I recently had occasion to get together with my family members. Let's see - there was my mother's sister-in-law, my mother's brother's daughter, my mother's brother's son's daughters, my mother's brother's daughter's daughter and my mother's brother's daughter's daughter's daughter. Here's what I don't get. If my mother's brother's daughter is my cousin and my mother's brother's daughter's daughter is my cousin twice removed, then what relation is my mother's brother's daughter's daughter's daughter or my mother's brother's son's daughter's daughter? Are they my cousins thrice removed? What do you say?