The term 'the outer layer of the Earth' can be summarized by the word 'CRUST, ' which is the five-letter answer to the crossword puzzle. The Earth's CRUST is the solid, outermost layer of the planet and is composed of various elements including oxygen, silicon, aluminum, iron, calcium, sodium, potassium, and magnesium. It is the thinnest layer of the Earth, ranging from 5 to 70 kilometers in thickness. The CRUST is divided into two types: oceanic CRUST and continental CRUST. Oceanic CRUST is denser and thinner than continental CRUST and is found beneath the oceans. Continental CRUST is thicker and less dense and is found beneath the continents.