Atherosclerosis, or hardening of the arteries, is a condition in which plaque builds up inside the arteries. Plaque is made of cholesterol, fatty substances, cellular waste products, calcium and fibrin (a clotting material in the blood). Atherosclerosis is a type of arteriosclerosis.
The definition of comity means politeness or mutual courtesy. 1  The peaceful coexistence of most of the nations in North America is an example of comity.  An example of comity is when a classroom of children are all happily involved in a project.
(countable and uncountable, plural rigidities) 1  The quality or state of being rigid; want of pliability; the quality of resisting change of form; the amount of resistance with which a body opposes change of form.  Stiffness of appearance or manner; want of ease or elegance.