density
den.si.ty \'den(t)-s*t-e-\ n 1: the quality or state of being dense 2: the quantity per unit volume, unit area, or unit length : as 2a: the mass of a substance per unit volume 2b: the average number of individuals or units per space unit 3: STUPIDITY 4a: the degree of opacity of a translucent medium 4b: the common logarithm of the opacity