Bone char is a term used for a type of carbon derived from animal bones which is commonly used in filtration processes. However, there are many synonyms for this term, each with their own unique connotations. Some of these synonyms include bone black, bone charcoal, animal charcoal, ivory black, and black bone. These terms all refer to carbon that has been produced by burning animal bones, and are commonly used in industries such as agriculture, sugar refining, and water purification. While the use of these terms may vary depending on the industry and region, they all refer to the same substance that is derived from animal bones.