The term 'Polar Coverings' refers to the icecaps that are found at the poles of the Earth. The most common crossword solution for this term is 'Icecaps', which is a seven-letter word. Icecaps are large masses of ice and snow that cover the land at the poles, and they are an important part of the Earth's climate system. They help regulate global temperatures by reflecting sunlight back into space, and they also contain vast amounts of freshwater.