A rongeur is a strongly constructed instrument with a sharp-edged, scoop-shaped tip, used for gouging out bone. Rongeur is a Frenchword that means rodent or 'gnawer'. A rongeur can be used to open a window in bone, often in the skull.
A rongeur is also used in oral maxillofacial surgery to remove bony fragments or soft tissue.
It is also used in hand surgery to cut traumatic amputated bone to allow skin to be closed over the defect