sequestra

noun, plural se·ques·tra [si-kwes-truh] /sɪˈkwɛs trə/. Pathology.

1. a fragment of bone that has become necrotic as a result of disease or injury and has separated from the normal bone structure.

noun plural -tra (-trə)

1. pathol a detached piece of necrotic bone that often migrates to a wound, abscess, etcSee sequester

n. pl. se•ques•tra (-trə)

1. A fragment of dead tissue, usually bone, that has separated from healthy tissue as a result of injury or disease.