The Collaborative International Dictionary of English v.0.48:

Plant \Plant\, n. [AS. plante, L. planta.]
   1. A vegetable; an organized living being, generally without
      feeling and voluntary motion, and having, when complete, a
      root, stem, and leaves, though consisting sometimes only
      of a single leafy expansion, or a series of cellules, or
      even a single cellule.
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   Note: Plants are divided by their structure and methods of
         reproduction into two series, ph[ae]nogamous or
         flowering plants, which have true flowers and seeds,
         and cryptogamous or flowerless plants, which have no
         flowers, and reproduce by minute one-celled spores. In
         both series are minute and simple forms and others of
         great size and complexity.
         [1913 Webster] As to their mode of nutrition, plants
         may be considered as self-supporting and dependent.
         Self-supporting plants always contain chlorophyll, and
         subsist on air and moisture and the matter dissolved in
         moisture, and as a general rule they excrete oxygen,
         and use the carbonic acid to combine with water and
         form the material for their tissues. Dependent plants
         comprise all fungi and many flowering plants of a
         parasitic or saprophytic nature. As a rule, they have
         no chlorophyll, and subsist mainly or wholly on matter
         already organized, thus utilizing carbon compounds
         already existing, and not excreting oxygen. But there
         are plants which are partly dependent and partly
         self-supporting.
         [1913 Webster] The movements of climbing plants, of
         some insectivorous plants, of leaves, stamens, or
         pistils in certain plants, and the ciliary motion of
         zoospores, etc., may be considered a kind of voluntary
         motion.
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   2. A bush, or young tree; a sapling; hence, a stick or staff.
      "A plant of stubborn oak." --Dryden.
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   3. The sole of the foot. [R.] "Knotty legs and plants of
      clay." --B. Jonson.
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   4. (Com.) The whole machinery and apparatus employed in
      carrying on a trade or mechanical business; also,
      sometimes including real estate, and whatever represents
      investment of capital in the means of carrying on a
      business, but not including material worked upon or
      finished products; as, the plant of a foundry, a mill, or
      a railroad.
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   5. A plan; an artifice; a swindle; a trick. [Slang]
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            It was n't a bad plant, that of mine, on Fikey.
                                                  --Dickens.
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   6. (Zool.)
      (a) An oyster which has been bedded, in distinction from
          one of natural growth.
      (b) A young oyster suitable for transplanting. [Local,
          U.S.]
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   Plant bug (Zool.), any one of numerous hemipterous insects
      which injure the foliage of plants, as Lygus lineolaris,
      which damages wheat and trees.

   Plant cutter (Zool.), a South American passerine bird of
      the genus Phytotoma, family Phytotomid[ae]. It has a
      serrated bill with which it cuts off the young shoots and
      buds of plants, often doing much injury.

   Plant louse (Zool.), any small hemipterous insect which
      infests plants, especially those of the families
      Aphid[ae] and Psyllid[ae]; an aphid.
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WordNet (r) 3.0 (2006):

Lygus lineolaris
    n 1: widespread plant and fruit pest [syn: tarnished plant
         bug, Lygus lineolaris]