A venogram is a diagnostic test that uses X-rays and a contrast material to examine the veins in the body. There are a variety of synonyms that describe this procedure, including venography, phlebography, and venous angiography. Venography involves injecting a contrast material into the veins to make them visible in X-ray images. Phlebography uses a similar technique to examine veins, but focuses on the deep venous system. Venous angiography is a more specific term that refers to the use of X-rays to study the flow of blood through veins. These synonyms are often used interchangeably and can refer to both diagnostic and therapeutic procedures.