Source : Webster's Revised Unabridged Dictionary (1913)

Fever \Fe"ver\, n. [OE. fever, fefer, AS. fefer, fefor, L.
   febris: cf. F. fi[`e]vre. Cf. {Febrile}.]
   1. (Med.) A diseased state of the system, marked by increased
      heat, acceleration of the pulse, and a general derangement
      of the functions, including usually, thirst and loss of
      appetite. Many diseases, of which fever is the most
      prominent symptom, are denominated fevers; as, typhoid
      fever; yellow fever.

   Note: Remitting fevers subside or abate at intervals;
         intermitting fevers intermit or entirely cease at
         intervals; continued or continual fevers neither remit
         nor intermit.

   2. Excessive excitement of the passions in consequence of
      strong emotion; a condition of great excitement; as, this
      quarrel has set my blood in a fever.

            An envious fever Of pale and bloodless emulation.
                                                  --Shak.

            After life's fitful fever he sleeps well. --Shak.

   {Brain fever}, {Continued fever}, etc. See under {Brain},
      {Continued}, etc.

   {Fever and ague}, a form of fever recurring in paroxysms
      which are preceded by chills. It is of malarial origin.

   {Fever blister} (Med.), a blister or vesicle often found
      about the mouth in febrile states; a variety of herpes.

   {Fever bush} (Bot.), the wild allspice or spice bush. See
      {Spicewood}.

   {Fever powder}. Same as {Jame's powder}.

   {Fever root} (Bot.), an American herb of the genus
      {Triosteum} ({T. perfoliatum}); -- called also {feverwort}
      amd {horse gentian}.

   {Fever sore}, a carious ulcer or necrosis. --Miner.

Brain \Brain\, n. [OE. brain, brein, AS. bragen, br[ae]gen; akin
   to LG. br["a]gen, bregen, D. brein, and perh. to Gr. ?, the
   upper part of head, if ? =?. [root]95.]
   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. (Zo["o]l.) The anterior or cephalic ganglion in insects
      and other invertebrates.

   3. The organ or seat of intellect; hence, the understanding.
      `` My brain is too dull.'' --Sir W. Scott.

   Note: In this sense, often used in the plural.

   4. The affections; fancy; imagination. [R.] --Shak.

   {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} (Zo["o]l), 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
      {M[ae]andrina} 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.

Source : WordNet®

brain fever
     n : meningitis caused by bacteria and often fatal [syn: {cerebrospinal
         meningitis}, {epidemic meningitis}, {cerebrospinal fever}]