WordWeb Online

1. Generally any arch shaped structure (but often it refers to the arched roof of an anatomical space)
    
2. An arched bundle of white fibers at the base of the brain by which the hippocampus of each hemisphere projects to the contralateral hippocampus and to the thalamus and mamillary bodies
   - trigonum cerebrale

Derived forms: fornices

Type of: body part, fascicle, fasciculus, fiber bundle [US], fibre bundle [Brit, Cdn]

Part of: limbic brain, limbic system, visceral brain

Encyclopedia: Fornix