midclavicular line /mid′kləvik″yo͝olər/ [AS, midd + L, clavicula, little key, linea, line] , (in anatomy) an imaginary line that extends downward over the trunk from the midpoint of the clavicle, dividing each side of the anterior chest into two parts. The left midclavicular line is an important marker in describing the location of various cardiac phenomena, including the point of maximum impulse.
