Brain n.
 1. Anat. The whitish mass of soft matter (the center of the nervous system, and the seat of consciousness and volition) which is inclosed in the cartilaginous or bony cranium of vertebrate animals. It is simply the anterior termination of the spinal cord, and is developed from three embryonic vesicles, whose cavities are connected with the central canal of the cord; the cavities of the vesicles become the central cavities, or ventricles, and the walls thicken unequally and become the three segments, the fore-, mid-, and hind-brain.
 Note: ☞ In the brain of man the cerebral lobes, or largest part of the forebrain, are enormously developed so as to overhang the cerebellum, the great lobe of the hindbrain, and completely cover the lobes of the midbrain. The surface of the cerebrum is divided into irregular ridges, or convolutions, separated by grooves (the so-called fissures and sulci), and the two hemispheres are connected at the bottom of the longitudinal fissure by a great transverse band of nervous matter, the corpus callosum, while the two halves of the cerebellum are connected on the under side of the brain by the bridge, or pons Varolii.
 2. Zool. The anterior or cephalic ganglion in insects and other invertebrates.
 3. The organ or seat of intellect; hence, the understanding; as, use your brains. “ My brain is too dull.”
 Note: ☞ In this sense, often used in the plural.
 4. The affections; fancy; imagination. [R.]
 To have on the brain, to have constantly in one's thoughts, as a sort of monomania. [Low]
 no-brainer a decision requiring little or no thought; an obvious choice. [slang]
 Brain box or  Brain case, the bony or cartilaginous case inclosing the brain.
 Brain coral, Brain stone coral Zool., 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.


 Cor·al n.
 1. Zool. The hard parts or skeleton of various Anthozoa, and of a few Hydrozoa. Similar structures are also formed by some Bryozoa.
 Note: ☞ The large stony corals forming coral reefs belong to various genera of Madreporaria, and to the hydroid genus, Millepora. The red coral, used in jewelry, is the stony axis of the stem of a gorgonian (Corallium rubrum) found chiefly in the Mediterranean. The fan corals, plume corals, and sea feathers are species of Gorgoniacea, in which the axis is horny. Organ-pipe coral is formed by the genus Tubipora, an Alcyonarian, and black coral is in part the axis of species of the genus Antipathes. See Anthozoa, Madrepora.
 2. The ovaries of a cooked lobster; -- so called from their color.
 3. A piece of coral, usually fitted with small bells and other appurtenances, used by children as a plaything.
 Brain coral, or Brain stone coral. See under Brain.
 Chain coral. See under Chain.
 Coral animal Zool., one of the polyps by which corals are formed. They are often very erroneously called coral insects.
 Coral fish. See in the Vocabulary.
 Coral reefs Phys. Geog., reefs, often of great extent, made up chiefly of fragments of corals, coral sands, and the solid limestone resulting from their consolidation. They are classed as fringing reefs, when they border the land; barrier reefs, when separated from the shore by a broad belt of water; atolls, when they constitute separate islands, usually inclosing a lagoon. See Atoll.
 Coral root Bot., a genus (Corallorhiza) of orchideous plants, of a yellowish or brownish red color, parasitic on roots of other plants, and having curious jointed or knotted roots not unlike some kinds of coral. See Illust. under Coralloid.
 Coral snake. Zo (a) A small, venomous, Brazilian snake (Elaps corallinus), coral-red, with black bands. (b) A small, harmless, South American snake (Tortrix scytale).
 Coral tree Bot., a tropical, leguminous plant, of several species, with showy, scarlet blossoms and coral-red seeds. The best known is Erythrina Corallodendron.
 Coral wood, a hard, red cabinet wood. --McElrath.

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