The term MATERIAL STAR can be broken down into two crossword solutions: TIN (3 letters) and STAR. TIN is a chemical element with the symbol Sn and atomic number 50. It is a malleable, ductile, and highly crystalline silvery-white metal. TIN is most commonly used in alloys such as bronze and pewter, and is also used to coat other metals to prevent corrosion. STAR is a luminous celestial body consisting of a mass of gas held together by its own gravity. Stars are the most widely recognized astronomical objects, and represent the most fundamental building blocks of galaxies.