The crossword solution for the term 'LOWER DOWN' is INFRA, which is a five-letter Latin word meaning 'BELOW'. It is commonly used in English to refer to something that is situated beneath or lower than something else. In architecture, it is used to describe the lowest level of a building, such as a basement or cellar. In biology, it is used to describe the parts of an organism that are located BELOW the surface, such as the roots of a plant. In geology, it is used to describe the layers of rock that are located beneath the surface of the Earth.