To have on the brain, to have constantly in one's thoughts, as a sort of monomania. [Low]
Brain box or case, the bony on cartilaginous case inclosing the brain. -- Brain coral, Brain stone coral (Zoöl), a massive reef-building coral having the surface covered by ridges separated by furrows so as to resemble somewhat the surface of the brain, esp. such corals of the genera Mæandrina and Diploria. -- Brain fag (Med.), brain weariness. See Cerebropathy. -- Brain fever (Med.), fever in which the brain is specially affected; any acute cerebral affection attended by fever. -- Brain sand, calcareous matter found in the pineal gland.