NCI Dictionary of Cancer Terms
The NCI Dictionary of Cancer Terms features 7,804 terms related to cancer and medicine.
Browse the dictionary by selecting a letter of the alphabet or by entering a cancer-related word or phrase in the search box.
- listen (vy-A-gruh)
- A drug used to treat erectile dysfunction. Viagra relaxes the smooth muscle of the penis to allow increased blood flow and erection. It is a type of phosphodiesterase inhibitor. Also called sildenafil.