What is the definition or description of: transvaginal ultrasound?

TVUS: Transvaginal ultrasound is an ultrasound examination where the ultrasound probe is placed into the vagina. It is often used to visualize structures that are difficult to see from the abdomen (uterus, bladder, ureters).

Ultrasound : An ultrasound is an imaging study in which a probe emits and receives sound waves which rebound off of internal organs in order to visualize them. For a transvaginal ultrasound a specially designed probe is lubricated and placed into the vagina in order to better visualize pelvic organs/ structures.