The term 'bottom of the sea' can be summarized by the crossword solution 'seabed, ' which is a six-letter word. The seabed is the floor of the ocean, and it is composed of sand, mud, rocks, and other materials. It is home to a variety of marine life, and its depths can reach up to 11, 000 meters. The seabed is an important part of the ocean ecosystem, and it plays a vital role in the global climate system.