Urology and Nephrology Practice Test 2026 - Free Urology and Nephrology Practice Questions and Study Guide

The combining form that means vas deferens is vas/o. In medical terminology, vas/o is used for the vas deferens, the duct that transports sperm from the epididymis toward the urethra. This root underpins terms like vas deferens and vasectomy, which are all about that specific duct. The other roots point to different structures or substances: vesicul/o relates to vesicles (such as the seminal vesicles), albumin/o to the protein albumin, and azot/o to nitrogen-containing substances. So vas/o is the one that specifically denotes the vas deferens.