Source : Webster's Revised Unabridged Dictionary (1913)

Mercury \Mer"cu*ry\, n. [L. Mercurius; akin to merx wares.]
   1. (Rom. Myth.) A Latin god of commerce and gain; -- treated
      by the poets as identical with the Greek Hermes, messenger
      of the gods, conductor of souls to the lower world, and
      god of eloquence.

   2. (Chem.) A metallic element mostly obtained by reduction
      from cinnabar, one of its ores. It is a heavy, opaque,
      glistening liquid (commonly called {quicksilver}), and is
      used in barometers, thermometers, ect. Specific gravity
      13.6. Symbol Hg (Hydrargyrum). Atomic weight 199.8.
      Mercury has a molecule which consists of only one atom. It
      was named by the alchemists after the god Mercury, and
      designated by his symbol, [mercury].

   Note: Mercury forms alloys, called amalgams, with many
         metals, and is thus used in applying tin foil to the
         backs of mirrors, and in extracting gold and silver
         from their ores. It is poisonous, and is used in
         medicine in the free state as in blue pill, and in its
         compounds as calomel, corrosive sublimate, etc. It is
         the only metal which is liquid at ordinary
         temperatures, and it solidifies at about -39[deg]
         Centigrade to a soft, malleable, ductile metal.

   3. (Astron.) One of the planets of the solar system, being
      the one nearest the sun, from which its mean distance is
      about 36,000,000 miles. Its period is 88 days, and its
      diameter 3,000 miles.

   4. A carrier of tidings; a newsboy; a messenger; hence, also,
      a newspaper. --Sir J. Stephen. ``The monthly Mercuries.''
      --Macaulay.

   5. Sprightly or mercurial quality; spirit; mutability;
      fickleness. [Obs.]

            He was so full of mercury that he could not fix long
            in any friendship, or to any design.  --Bp. Burnet.

   6. (Bot.) A plant ({Mercurialis annua}), of the Spurge
      family, the leaves of which are sometimes used for
      spinach, in Europe.

   Note: The name is also applied, in the United States, to
         certain climbing plants, some of which are poisonous to
         the skin, esp. to the {Rhus Toxicodendron}, or poison
         ivy.

   {Dog's mercury} (Bot.), {Mercurialis perennis}, a perennial
      plant differing from {M. annua} by having the leaves
      sessile.

   {English mercury} (Bot.), a kind of goosefoot formerly used
      as a pot herb; -- called {Good King Henry}.

   {Horn mercury} (Min.), a mineral chloride of mercury, having
      a semitranslucent, hornlike appearance.

Ivy \I"vy\, n.; pl. {Ivies}. [AS. [=i]fig; akin to OHG. ebawi,
   ebah, G. epheu.] (Bot.)
   A plant of the genus {Hedera} ({H. helix}), common in Europe.
   Its leaves are evergreen, dark, smooth, shining, and mostly
   five-pointed; the flowers yellowish and small; the berries
   black or yellow. The stem clings to walls and trees by
   rootlike fibers.

         Direct The clasping ivy where to climb.  --Milton.

         Ye myrtles brown, with ivy never sere.   --Milton.

   {American ivy}. (Bot.) See {Virginia creeper}.

   {English ivy} (Bot.), a popular name in America for the ivy
      proper ({Hedera helix}).

   {German ivy} (Bot.), a creeping plant, with smooth, succulent
      stems, and fleshy, light-green leaves; a species of
      {Senecio} ({S. scandens}).

   {Ground ivy}. (Bot.) Gill ({Nepeta Glechoma}).

   {Ivy bush}. (Bot.) See {Mountain laurel}, under {Mountain}.
      

   {Ivy owl} (Zo["o]l.), the barn owl.

   {Ivy tod} (Bot.), the ivy plant. --Tennyson.

   {Japanese ivy} (Bot.), a climbing plant ({Ampelopsis
      tricuspidata}), closely related to the Virginia creeper.
      

   {Poison ivy} (Bot.), an American woody creeper ({Rhus
      Toxicodendron}), with trifoliate leaves, and
      greenish-white berries. It is exceedingly poisonous to the
      touch for most persons.

   {To pipe in an ivy leaf}, to console one's self as best one
      can. [Obs.] --Chaucer.

   {West Indian ivy}, a climbing plant of the genus
      {Marcgravia}.

Poison \Poi"son\, n. [F. poison, in Old French also, a potion,
   fr. L. potio a drink, draught, potion, a poisonous draught,
   fr. potare to drink. See {Potable}, and cf. {Potion}.]
   1. Any agent which, when introduced into the animal organism,
      is capable of producing a morbid, noxious, or deadly
      effect upon it; as, morphine is a deadly poison; the
      poison of pestilential diseases.

   2. That which taints or destroys moral purity or health; as,
      the poison of evil example; the poison of sin.

   {Poison ash}. (Bot.)
      (a) A tree of the genus {Amyris} ({A. balsamifera}) found
          in the West Indies, from the trunk of which a black
          liquor distills, supposed to have poisonous qualities.
      (b) The poison sumac ({Rhus venenata}). [U. S.]

   {Poison dogwood} (Bot.), poison sumac.

   {Poison fang} (Zo["o]l.), one of the superior maxillary teeth
      of some species of serpents, which, besides having the
      cavity for the pulp, is either perforated or grooved by a
      longitudinal canal, at the lower end of which the duct of
      the poison gland terminates. See Illust. under {Fang}.

   {Poison gland} (Biol.), a gland, in animals or plants, which
      secretes an acrid or venomous matter, that is conveyed
      along an organ capable of inflicting a wound.

   {Poison hemlock} (Bot.), a poisonous umbelliferous plant
      ({Conium maculatum}). See {Hemlock}.

   {Poison ivy} (Bot.), a poisonous climbing plant ({Rhus
      Toxicodendron}) of North America. It is common on stone
      walls and on the trunks of trees, and has trifoliate,
      rhombic-ovate, variously notched leaves. Many people are
      poisoned by it, if they touch the leaves. See {Poison
      sumac}. Called also {poison oak}, and {mercury}.

   {Poison nut}. (Bot.)
      (a) Nux vomica.
      (b) The tree which yields this seed ({Strychnos
          Nuxvomica}). It is found on the Malabar and Coromandel
          coasts.

   {Poison oak} (Bot.), the poison ivy; also, the more shrubby
      {Rhus diversiloba} of California and Oregon.

   {Poison sac}. (Zo["o]l.) Same as {Poison gland}, above. See
      Illust. under {Fang}.

   {Poison sumac} (Bot.), a poisonous shrub of the genus {Rhus}
      ({R. venenata}); -- also called {poison ash}, {poison
      dogwood}, and {poison elder}. It has pinnate leaves on
      graceful and slender common petioles, and usually grows in
      swampy places. Both this plant and the poison ivy ({Rhus
      Toxicodendron}) have clusters of smooth greenish white
      berries, while the red-fruited species of this genus are
      harmless. The tree ({Rhus vernicifera}) which yields the
      celebrated Japan lacquer is almost identical with the
      poison sumac, and is also very poisonous. The juice of the
      poison sumac also forms a lacquer similar to that of
      Japan.

   Syn: Venom; virus; bane; pest; malignity.

   Usage: {Poison}, {Venom}. Poison usually denotes something
          received into the system by the mouth, breath, etc.
          Venom is something discharged from animals and
          received by means of a wound, as by the bite or sting
          of serpents, scorpions, etc. Hence, venom specifically
          implies some malignity of nature or purpose.

Poison \Poi"son\, n. [F. poison, in Old French also, a potion,
   fr. L. potio a drink, draught, potion, a poisonous draught,
   fr. potare to drink. See {Potable}, and cf. {Potion}.]
   1. Any agent which, when introduced into the animal organism,
      is capable of producing a morbid, noxious, or deadly
      effect upon it; as, morphine is a deadly poison; the
      poison of pestilential diseases.

   2. That which taints or destroys moral purity or health; as,
      the poison of evil example; the poison of sin.

   {Poison ash}. (Bot.)
      (a) A tree of the genus {Amyris} ({A. balsamifera}) found
          in the West Indies, from the trunk of which a black
          liquor distills, supposed to have poisonous qualities.
      (b) The poison sumac ({Rhus venenata}). [U. S.]

   {Poison dogwood} (Bot.), poison sumac.

   {Poison fang} (Zo["o]l.), one of the superior maxillary teeth
      of some species of serpents, which, besides having the
      cavity for the pulp, is either perforated or grooved by a
      longitudinal canal, at the lower end of which the duct of
      the poison gland terminates. See Illust. under {Fang}.

   {Poison gland} (Biol.), a gland, in animals or plants, which
      secretes an acrid or venomous matter, that is conveyed
      along an organ capable of inflicting a wound.

   {Poison hemlock} (Bot.), a poisonous umbelliferous plant
      ({Conium maculatum}). See {Hemlock}.

   {Poison ivy} (Bot.), a poisonous climbing plant ({Rhus
      Toxicodendron}) of North America. It is common on stone
      walls and on the trunks of trees, and has trifoliate,
      rhombic-ovate, variously notched leaves. Many people are
      poisoned by it, if they touch the leaves. See {Poison
      sumac}. Called also {poison oak}, and {mercury}.

   {Poison nut}. (Bot.)
      (a) Nux vomica.
      (b) The tree which yields this seed ({Strychnos
          Nuxvomica}). It is found on the Malabar and Coromandel
          coasts.

   {Poison oak} (Bot.), the poison ivy; also, the more shrubby
      {Rhus diversiloba} of California and Oregon.

   {Poison sac}. (Zo["o]l.) Same as {Poison gland}, above. See
      Illust. under {Fang}.

   {Poison sumac} (Bot.), a poisonous shrub of the genus {Rhus}
      ({R. venenata}); -- also called {poison ash}, {poison
      dogwood}, and {poison elder}. It has pinnate leaves on
      graceful and slender common petioles, and usually grows in
      swampy places. Both this plant and the poison ivy ({Rhus
      Toxicodendron}) have clusters of smooth greenish white
      berries, while the red-fruited species of this genus are
      harmless. The tree ({Rhus vernicifera}) which yields the
      celebrated Japan lacquer is almost identical with the
      poison sumac, and is also very poisonous. The juice of the
      poison sumac also forms a lacquer similar to that of
      Japan.

   Syn: Venom; virus; bane; pest; malignity.

   Usage: {Poison}, {Venom}. Poison usually denotes something
          received into the system by the mouth, breath, etc.
          Venom is something discharged from animals and
          received by means of a wound, as by the bite or sting
          of serpents, scorpions, etc. Hence, venom specifically
          implies some malignity of nature or purpose.