Source : Webster's Revised Unabridged Dictionary (1913)

Boil \Boil\ (boil), v. i. [imp. & p. p. {Boiled} (boild); p. pr.
   & vb. n. {Boiling}.] [OE. boilen, OF. boilir, builir, F.
   bouillir, fr. L. bullire to be in a bubbling motion, from
   bulla bubble; akin to Gr. ?, Lith. bumbuls. Cf. {Bull} an
   edict, {Budge}, v., and {Ebullition}.]
   1. To be agitated, or tumultuously moved, as a liquid by the
      generation and rising of bubbles of steam (or vapor), or
      of currents produced by heating it to the boiling point;
      to be in a state of ebullition; as, the water boils.

   2. To be agitated like boiling water, by any other cause than
      heat; to bubble; to effervesce; as, the boiling waves.

            He maketh the deep to boil like a pot. --Job xii.
                                                  31.

   3. To pass from a liquid to an a["e]riform state or vapor
      when heated; as, the water boils away.

   4. To be moved or excited with passion; to be hot or fervid;
      as, his blood boils with anger.

            Then boiled my breast with flame and burning wrath.
                                                  --Surrey.

   5. To be in boiling water, as in cooking; as, the potatoes
      are boiling.

   {To boil away}, to vaporize; to evaporate or be evaporated by
      the action of heat.

   {To boil over}, to run over the top of a vessel, as liquid
      when thrown into violent agitation by heat or other cause
      of effervescence; to be excited with ardor or passion so
      as to lose self-control.

Boil \Boil\, n.
   Act or state of boiling. [Colloq.]

Boil \Boil\, n. [Influenced by boil, v. See {Beal}, {Bile}.]
   A hard, painful, inflamed tumor, which, on suppuration,
   discharges pus, mixed with blood, and discloses a small
   fibrous mass of dead tissue, called the core.

   {A blind boil}, one that suppurates imperfectly, or fails to
      come to a head.

   {Delhi boil} (Med.), a peculiar affection of the skin,
      probably parasitic in origin, prevailing in India (as
      among the British troops) and especially at Delhi.

Boil \Boil\, v. t.
   1. To heat to the boiling point, or so as to cause
      ebullition; as, to boil water.

   2. To form, or separate, by boiling or evaporation; as, to
      boil sugar or salt.

   3. To subject to the action of heat in a boiling liquid so as
      to produce some specific effect, as cooking, cleansing,
      etc.; as, to boil meat; to boil clothes.

            The stomach cook is for the hall, And boileth meate
            for them all.                         --Gower.

   4. To steep or soak in warm water. [Obs.]

            To try whether seeds be old or new, the sense can
            not inform; but if you boil them in water, the new
            seeds will sprout sooner.             --Bacon.

   {To boil down}, to reduce in bulk by boiling; as, to boil
      down sap or sirup.

Source : WordNet®

boil
     n 1: a painful sore with a hard pus-filled core [syn: {furuncle}]
     2: the temperature at which a liquid boils at sea level; "the
        brought to water to a boil" [syn: {boiling point}]

boil
     v 1: come to the boiling point and change from a liquid to vapor;
          "Water boils at 100 degrees Celsius" [ant: {freeze}]
     2: cook in boiling liquid; "boil potatoes"
     3: bring to, or maintain at, the boiling point; "boil this
        liquid until it evaporates"
     4: be agitated; "the sea was churning in the storm" [syn: {churn},
         {moil}, {roil}]
     5: be in an agitated emotional state; "The customer was
        seething with anger" [syn: {seethe}]