Meridians refer to the pathways in the human body that run qi and blood and communicate up and down the entire body internally and externally. Blood vessels are the conduits through which the body transports substances and through which blood circulates.
Meridian is the concept of Chinese medicine. Meridian refers to the human body to run blood, contact internal organs, communication inside and outside, through the up and down the pathway, is the general term of the meridians and veins.
Blood vessels is the concept of modern medical anatomy, blood vessels, including arteries, veins, capillaries, and the heart together constitute the cardiovascular system, is the blood circulation in which the material transportation pipeline.
Blood vessels and meridians are two concepts in different medical systems. Blood vessels are anatomical concepts, while meridians cannot be observed visually through dissection, but are an abstract concept in Chinese medicine to guide the selection of acupuncture points and treatment.