Chitons are a type of marine mollusk that are characterized by their shells which consist of eight articulated plates. They are also known as coat-of-mail shells, for obvious reasons. If you're looking for synonyms for the word 'chitons', there are a few options available. One such synonym is polyplacophora, which is the scientific name for this group of mollusks. Another synonym is 'sea cradle', which refers to the way that chitons are anchored to rocks and other hard surfaces in the ocean. Additionally, some people may refer to chitons as 'rock shells', due to their appearance and habitat.