The term 'Building Clay' can be summarized by the crossword solution 'ADOBE', which is a type of building material made from sand, clay, water, and some kind of organic material such as straw or manure. ADOBE has been used for centuries to construct buildings in many parts of the world, including the Middle East, South America, and the American Southwest. It is a durable and sustainable material that is still used today in many parts of the world.