What does craniotomy mean?
Craniotomy is a noun referring to a major neurosurgical operation in which a surgeon removes a section of bone — called a bone flap — from the skull in order to reach the brain beneath. Once the necessary work is done, such as removing a tumour, draining a haematoma, or relieving pressure after trauma, the flap is usually secured back in place. The term derives from Greek roots: 'kranion', meaning skull, and 'tomia', meaning cut, so it literally describes cutting into the cranium. It appears almost exclusively in medical, scientific, and clinical writing rather than everyday conversation, and carries an inherently serious connotation because of the gravity of brain surgery. A closely related procedure is the craniectomy, in which the removed bone is not replaced — a distinction that matters clinically but is easy for lay readers to overlook. Variants such as awake craniotomy, performed while the patient is conscious, have become notable in modern practice for preserving speech and motor function during delicate operations.
nounA surgical operation in which a piece of the skull is removed to expose the brain, typically to treat conditions such as tumours, haemorrhage, or trauma.
- A surgical procedure in which part of the skull (a bone flap) is temporarily removed to access the brain, then usually replaced.
"The neurosurgeon performed a craniotomy to remove the tumour pressing on the optic nerve."
"She underwent an emergency craniotomy after the accident caused bleeding on the brain."
"Awake craniotomy allows surgeons to monitor speech and motor functions while removing tissue from critical areas of the brain."
Standard pluralisation following the -y → -ies pattern, as the word ends in a consonant plus y.
"The department performs several hundred craniotomies each year."
The word 'craniotomy' comes from Greek roots meaning literally 'cutting into the skull' — a procedure humans have attempted in some form for thousands of years, long before we had the vocabulary for it.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of craniotomy
Craniotomy derives from the Greek words 'kranion' (skull) and 'tome' or 'tomia' (a cutting), joined as a compound reflecting its literal meaning: a cutting into the skull. The word entered English medical vocabulary in the nineteenth century, when modern surgical terminology was being systematised using classical roots. It shares its '-otomy' suffix with many other surgical terms describing incision into a body part, and shares the 'crani-' root with words like 'cranium', 'cranial', and 'craniology'.
How craniotomy is actually used
A formal medical term used almost exclusively in clinical, surgical, or academic contexts. It refers specifically to accessing the brain through the skull; it is not used for procedures on the face or other parts of the head that do not involve opening the cranial cavity.
Easily confused with craniotomy
A craniotomy removes a flap of bone that is typically replaced at the end of the operation, whereas a craniectomy removes bone without replacing it.