Lithified sediment refers to sedimentary rocks that have been converted into solid, cohesive structures through the process of lithification. Synonyms for this term include cemented sediment, consolidated sediment, petrified sediment, and hardened sediment. All of these terms describe sedimentary rocks that have undergone the process of lithification and formed cohesive structures through the binding of particles with minerals such as calcite, silica, or iron. Lithified sediment is an important element in the study of geology, as it provides insight into the composition and history of the Earth's surface and helps scientists understand the processes that have shaped our planet over millions of years.