The Clue Greek letter used to represent density
The Answer RHO
The Greek letter "rho" is commonly used in science and mathematics to represent density. In physics, density is defined as mass per unit volume, and "rho" is the standard symbol for this concept. It is one of the many Greek letters that are used in various scientific fields. Therefore, "rho" fits perfectly as the answer to the crossword clue about a Greek letter representing density.