Concrement, a term most often used in dental and medical fields, refers to a hard, compact mass that forms in a particular part of the body. There are several other words that can be used to describe concrement, depending on the location or type of mass. The terms calculus, stone, nodule, and plaque are all used to describe concrement in various contexts. Calculus and stone are commonly used to describe concrement in the kidneys or gallbladder, whereas nodule is used for masses found in the skin or thyroid gland. Finally, plaque is often used to refer to concrement on teeth or in arteries.