#1 solid n. matter that is solid at room temperature and pressure. wn #2 solid s. characterized by good substantial quality; "solid comfort"; "a solid base hit". wn #3 solid a. of definite shape and volume; firm; neither liquid nor gaseous; "ice is water in the solid state". wn #4 solid a. entirely of one substance with no holes inside; "a solid block of wood". wn #5 solid s. of one substance or character throughout; "solid gold"; "carved out of solid rock". wn