The Haumea or Haumean family is the only identified trans-Neptunian collisional family; that is, the only group of trans-Neptunian objects (TNOs) with similar orbital parameters and spectra (nearly pure water-ice) that suggest they originated in the disruptive impact of a progenitor body.[1] Calculations indicate that it is probably the only trans-Neptunian collisional family.[2] Members are known as Haumeids.
Levison
was invoked but never defined (see the help page).