Martello is a term used to describe a type of coastal defense tower that was widely used in the early 19th century. The word originates from the Italian language and literally translates to "hammer". Although the term martello is often used to describe these defense towers, there are several synonyms that can also be used. Some examples of synonyms for martello include fortification, fortress, citadel, battlement, and stronghold. Each of these terms describes structures used for fortification, defense, and protection against attacks. Whether it's a martello tower or a fortress, these structures were instrumental in protecting coastlines and maritime regions from foreign threats.