noun

• (anatomy) An archlike or vaulted structure or fold:
• The junction where the conjunctiva lining the eyelid meets the conjunctiva overlying the sclera.
• (neuroanatomy) A triangular area of white matter in the mammalian brain beneath the corpus callosum and between the hippocampus and the hypothalamus.
• The vaulted upper part of the vagina surrounding the uterine cervix.