fornix has definitions from the fields of anatomy,zoology
1
[ noun ] generally any arch shaped structure (but often it refers to the arched roof of an anatomical space)

Related terms

body_part

2
[ noun ] (anatomy,zoology) 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
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