What does vasodilation mean?
Vasodilation is the widening of blood vessels when the smooth muscle in their walls relaxes. This process is especially important in small arteries and arterioles, where it can increase blood flow to a particular tissue and reduce the resistance against which the heart must pump. Vasodilation occurs naturally during exercise, in response to temperature changes, and as part of various physiological reflexes. It can also be induced by substances such as nitroglycerin, which is why vasodilators are important in treating certain cardiovascular conditions. The term is technical and appears frequently in medicine, physiology, pharmacology, and research. For general audiences, it can be explained more simply as the process that makes blood vessels wider and permits more blood to pass through them. Recognizing its role is useful when understanding how exercise affects circulation, how blood pressure is regulated, and how several familiar medicines produce their effects.
nounVasodilation is the widening of blood vessels, especially small arteries and arterioles, caused by relaxation of the smooth muscle in their walls. It increases local blood flow and can reduce vascular resistance.
- The physiological process in which blood vessels widen through relaxation of vascular smooth muscle, increasing local blood flow and often reducing vascular resistance.
"The drug promoted vasodilation, allowing more blood to reach the affected muscles."
"Exercise-induced vasodilation increases blood flow to working muscles by widening their small arteries and arterioles."
"The medication caused vasodilation, which reduced the heart's workload by improving blood flow through narrowed vessels."
The plural is uncommon because the process is usually treated as uncountable in scientific writing, although it is grammatically possible.
"The researchers observed vasodilations in the small arteries of both treatment groups."
When your cheeks turn pink after a spicy meal, vasodilation is widening the tiny blood vessels near the surface of your skin.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does vasodilation come from?
Vasodilation combines the Latin-derived element vaso-, meaning 'vessel,' with dilation, from Latin dilatare, meaning 'to widen or expand.' The compound belongs to a wider family of anatomical terms formed with vaso-, including vasoconstriction, vasomotor, and vasodilator, and its underlying roots describe the widening of vessels and the related Latin root dilat-, meaning 'broad' or 'expanded.'
Related word forms
How vasodilation is actually used
This is a formal scientific and medical term, especially common in physiology, pharmacology, and cardiovascular research. In British English, the spelling 'vasodilatation' is also widely used. In general prose, descriptions such as 'widening of blood vessels' may be more accessible.
Easily confused with vasodilation
Vasodilation is the process of a blood vessel widening, whereas a vasodilator is a substance or mechanism that causes this process.