Final answer:
The word that means pertaining to a vein is venous.
Step-by-step explanation:
The term derived from the combining form ven/o and the suffix -ous is "venous." This word specifically denotes a connection to or characteristics of veins within the body. In the realm of anatomy and physiology, "venous" refers to structures or processes related to veins, the blood vessels responsible for returning deoxygenated blood to the heart. Whether describing the circulatory system or medical conditions, such as venous insufficiency, the term "venous" encapsulates a nuanced understanding of vascular dynamics. By combining the linguistic components, this word elegantly conveys a precise and specialized meaning, facilitating clear communication in medical and scientific contexts.