Removal, Incision, or Opening

These pairs share a root but change meaning entirely with the ending.

Term	What happens
`tracheectomy`	removal of part or all of the trachea; uncommon compared with related airway procedures
`tracheotomy`	incision into the trachea
`tracheostomy`	creation or maintenance of an opening into the trachea
`colectomy`	removal of all or part of the colon
`colotomy`	incision into the colon
`colostomy`	creation of an opening from the colon

-ectomy takes out. -otomy cuts into. -stomy creates an opening. Similar sound, different action.