When adding ectomy to a root word what part of speech is created?

"-ectomy" is a suffix meaning "surgical removal".

Here are some examples:

* Appendicitis + ectomy = Appendectomy (surgical removal of the appendix)

* Tonsil + ectomy = Tonsillectomy (surgical removal of the tonsils)

* Hyster + ectomy = Hysterectomy (surgical removal of the uterus)