A perineal dilator is a medical device used to expand the vaginal opening during childbirth. There are various synonyms for the term "perineal dilator," which include "birthing tool," "vaginal dilator," "delivery device," and "obstetric dilator." Other synonyms include "perineal stretcher," "vaginal cerclage," "episiotomy instrument," and "birth canal expander." These terms may be used interchangeably, and they refer to the same medical device used to ease the delivery process. Although the primary use of perineal dilators is in obstetrics, they can be used in other areas such as gynecology and sexual medicine.