Source : Webster's Revised Unabridged Dictionary (1913)

Sweet \Sweet\, a. [Compar. {Sweeter}; superl. {Sweetest}.] [OE.
   swete, swote, sote, AS. sw[=e]te; akin to OFries. sw[=e]te,
   OS. sw[=o]ti, D. zoet, G. s["u]ss, OHG. suozi, Icel. s[ae]tr,
   s[oe]tr, Sw. s["o]t, Dan. s["o]d, Goth. suts, L. suavis, for
   suadvis, Gr. ?, Skr. sv[=a]du sweet, svad, sv[=a]d, to
   sweeten. [root]175. Cf. {Assuage}, {Suave}, {Suasion}.]
   1. Having an agreeable taste or flavor such as that of sugar;
      saccharine; -- opposed to sour and bitter; as, a sweet
      beverage; sweet fruits; sweet oranges.

   2. Pleasing to the smell; fragrant; redolent; balmy; as, a
      sweet rose; sweet odor; sweet incense.

            The breath of these flowers is sweet to me.
                                                  --Longfellow.

   3. Pleasing to the ear; soft; melodious; harmonious; as, the
      sweet notes of a flute or an organ; sweet music; a sweet
      voice; a sweet singer.

            To make his English sweet upon his tongue.
                                                  --Chaucer.

            A voice sweet, tremulous, but powerful. --Hawthorne.

   4. Pleasing to the eye; beautiful; mild and attractive; fair;
      as, a sweet face; a sweet color or complexion.

            Sweet interchange Of hill and valley, rivers, woods,
            and plains.                           --Milton.

   5. Fresh; not salt or brackish; as, sweet water. --Bacon.

   6. Not changed from a sound or wholesome state. Specifically:
      (a) Not sour; as, sweet milk or bread.
      (b) Not state; not putrescent or putrid; not rancid; as,
          sweet butter; sweet meat or fish.

   7. Plaesing to the mind; mild; gentle; calm; amiable;
      winning; presuasive; as, sweet manners.

            Canst thou bind the sweet influence of Pleiades?
                                                  --Job xxxviii.
                                                  31.

            Mildness and sweet reasonableness is the one
            established rule of Christian working. --M. Arnold.

   Note: Sweet is often used in the formation of self-explaining
         compounds; as, sweet-blossomed, sweet-featured,
         sweet-smelling, sweet-tempered, sweet-toned, etc.

   {Sweet alyssum}. (Bot.) See {Alyssum}.

   {Sweet apple}. (Bot.)
      (a) Any apple of sweet flavor.
      (b) See {Sweet-top}.

   {Sweet bay}. (Bot.)
      (a) The laurel ({laurus nobilis}).
      (b) Swamp sassafras.

   {Sweet calabash} (Bot.), a plant of the genus {Passiflora}
      ({P. maliformis}) growing in the West Indies, and
      producing a roundish, edible fruit, the size of an apple.
      

   {Sweet cicely}. (Bot.)
      (a) Either of the North American plants of the
          umbelliferous genus {Osmorrhiza} having aromatic roots
          and seeds, and white flowers. --Gray.
      (b) A plant of the genus {Myrrhis} ({M. odorata}) growing
          in England.

   {Sweet calamus}, or {Sweet cane}. (Bot.) Same as {Sweet
      flag}, below.

   {Sweet Cistus} (Bot.), an evergreen shrub ({Cistus Ladanum})
      from which the gum ladanum is obtained.

   {Sweet clover}. (Bot.) See {Melilot}.

   {Sweet coltsfoot} (Bot.), a kind of butterbur ({Petasites
      sagittata}) found in Western North America.

   {Sweet corn} (Bot.), a variety of the maize of a sweet taste.
      See the Note under {Corn}.

   {Sweet fern} (Bot.), a small North American shrub
      ({Comptonia, or Myrica, asplenifolia}) having
      sweet-scented or aromatic leaves resembling fern leaves.
      

   {Sweet flag} (Bot.), an endogenous plant ({Acorus Calamus})
      having long flaglike leaves and a rootstock of a pungent
      aromatic taste. It is found in wet places in Europe and
      America. See {Calamus}, 2.

   {Sweet gale} (Bot.), a shrub ({Myrica Gale}) having bitter
      fragrant leaves; -- also called {sweet willow}, and {Dutch
      myrtle}. See 5th {Gale}.

   {Sweet grass} (Bot.), holy, or Seneca, grass.

   {Sweet gum} (Bot.), an American tree ({Liquidambar
      styraciflua}). See {Liquidambar}.

   {Sweet herbs}, fragrant herbs cultivated for culinary
      purposes.

   {Sweet John} (Bot.), a variety of the sweet William.

   {Sweet leaf} (Bot.), horse sugar. See under {Horse}.

   {Sweet marjoram}. (Bot.) See {Marjoram}.

   {Sweet marten} (Zo["o]l.), the pine marten.

   {Sweet maudlin} (Bot.), a composite plant ({Achillea
      Ageratum}) allied to milfoil.

   {Sweet oil}, olive oil.

   {Sweet pea}. (Bot.) See under {Pea}.

   {Sweet potato}. (Bot.) See under {Potato}.

   {Sweet rush} (Bot.), sweet flag.

   {Sweet spirits of niter} (Med. Chem.) See {Spirit of nitrous
      ether}, under {Spirit}.

   {Sweet sultan} (Bot.), an annual composite plant ({Centaurea
      moschata}), also, the yellow-flowered ({C. odorata}); --
      called also {sultan flower}.

   {Sweet tooth}, an especial fondness for sweet things or for
      sweetmeats. [Colloq.]

   {Sweet William}.
      (a) (Bot.) A species of pink ({Dianthus barbatus}) of many
          varieties.
      (b) (Zo["o]l.) The willow warbler.
      (c) (Zo["o]l.) The European goldfinch; -- called also
          {sweet Billy}. [Prov. Eng.]

   {Sweet willow} (Bot.), sweet gale.

   {Sweet wine}. See {Dry wine}, under {Dry}.

   {To be sweet on}, to have a particular fondness for, or
      special interest in, as a young man for a young woman.
      [Colloq.] --Thackeray.

   Syn: Sugary; saccharine; dulcet; luscious.

Source : WordNet®

Acorus calamus
     n : perennial marsh plant having swordlike leaves and aromatic
         roots [syn: {sweet flag}, {calamus}, {sweet calamus}, {myrtle
         flag}, {flagroot}]