The Collaborative International Dictionary of English v.0.48:

Crop \Crop\, v. i.
   To yield harvest.
   [1913 Webster]

   To crop out.
   (a) (Geol.) To appear above the surface, as a seam or vein,
       or inclined bed, as of coal.
   (b) To come to light; to be manifest; to appear; as, the
       peculiarities of an author crop out.

   To crop up, to sprout; to spring up; to appear suddenly.
      "Cares crop up in villas." --Beaconsfield.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Crop \Crop\ (kr[o^]p), n. [OE. crop, croppe, craw, top of a
   plant, harvest, AS. crop, cropp, craw, top, bunch, ear of
   corn; akin to D. krop craw, G. kropf, Icel. kroppr hump or
   bunch on the body, body; but cf. also W. cropa, croppa, crop
   or craw of a bird, Ir. & Gael. sgroban. Cf. Croup,
   Crupper, Croup.]
   1. The pouchlike enlargement of the gullet of birds, serving
      as a receptacle for food; the craw.
      [1913 Webster]

   2. The top, end, or highest part of anything, especially of a
      plant or tree. [Obs.] "Crop and root." --Chaucer.
      [1913 Webster]

   3. That which is cropped, cut, or gathered from a single
      felld, or of a single kind of grain or fruit, or in a
      single season; especially, the product of what is planted
      in the earth; fruit; harvest.
      [1913 Webster]

            Lab'ring the soil, and reaping plenteous crop,
            Corn, wine, and oil.                  --Milton.
      [1913 Webster]

   4. Grain or other product of the field while standing.
      [1913 Webster]

   5. Anything cut off or gathered.
      [1913 Webster]

            Guiltless of steel, and from the razor free,
            It falls a plenteous crop reserved for thee.
                                                  --Dryden.
      [1913 Webster]

   6. Hair cut close or short, or the act or style of so
      cutting; as, a convict's crop.
      [1913 Webster]

   7. (Arch.) A projecting ornament in carved stone.
      Specifically, a finial. [Obs.]
      [1913 Webster]

   8. (Mining.)
      (a) Tin ore prepared for smelting.
      (b) Outcrop of a vein or seam at the surface. --Knight.
          [1913 Webster]

   9. A riding whip with a loop instead of a lash.
      [1913 Webster]

   Neck and crop, altogether; roughly and at once. [Colloq.]
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Crop \Crop\, v. t. [imp. & p. p. Cropped (kr[o^]pt); p. pr. &
   vb. n. Cropping.]
   1. To cut off the tops or tips of; to bite or pull off; to
      browse; to pluck; to mow; to reap.
      [1913 Webster]

            I will crop off from the top of his young twigs a
            tender one.                           --Ezek. xvii.
                                                  22.
      [1913 Webster]

   2. Fig.: To cut off, as if in harvest.
      [1913 Webster]

            Death . . . .crops the growing boys. --Creech.
      [1913 Webster]

   3. To cause to bear a crop; as, to crop a field.
      [1913 Webster]

   4. to cut off an unnecessary portion at the edges; -- of
      photographs and other two-dimensional images; as, to crop
      her photograph up to the shoulders.
      [PJC]

WordNet (r) 3.0 (2006):

crop
    n 1: the yield from plants in a single growing season [syn:
         crop, harvest]
    2: a cultivated plant that is grown commercially on a large
       scale
    3: a collection of people or things appearing together; "the
       annual crop of students brings a new crop of ideas"
    4: the output of something in a season; "the latest crop of
       fashions is about to hit the stores"
    5: the stock or handle of a whip
    6: a pouch in many birds and some lower animals that resembles a
       stomach for storage and preliminary maceration of food [syn:
       craw, crop]
    v 1: cut short; "She wanted her hair cropped short"
    2: prepare for crops; "Work the soil"; "cultivate the land"
       [syn: cultivate, crop, work]
    3: yield crops; "This land crops well"
    4: let feed in a field or pasture or meadow [syn: crop,
       graze, pasture]
    5: feed as in a meadow or pasture; "the herd was grazing" [syn:
       crop, browse, graze, range, pasture]
    6: cultivate, tend, and cut back the growth of; "dress the
       plants in the garden" [syn: snip, clip, crop, trim,
       lop, dress, prune, cut back]