The Collaborative International Dictionary of English v.0.48:

Dwarf \Dwarf\, n.; pl. Dwarfs. [OE. dwergh, dwerf, dwarf, AS.
   dweorg, dweorh; akin to D. dwerg, MHG. twerc, G. zwerg, Icel.
   dvergr, Sw. & Dan. dverg; of unknown origin.]
   1. An animal or plant which is much below the ordinary size
      of its species or kind.
      [1913 Webster]

   2. Especially: A diminutive human being, small in stature due
      to a pathological condition which causes a distortion of
      the proportions of body parts to each other, such as the
      limbs, torso, and head. A person of unusually small height
      who has normal body proportions is usually called a
      midget.
      [PJC]

   Note: During the Middle Ages dwarfs as well as fools shared
         the favor of courts and the nobility.
         [1913 Webster]

   3. (Folklore) A small, usually misshapen person, typically a
      man, who may have magical powers; mythical dwarves were
      often depicted as living underground in caves.
      [PJC]

   Note: Dwarf is used adjectively in reference to anything much
         below the usual or normal size; as, a dwarf pear tree;
         dwarf honeysuckle.
         [1913 Webster]

   Dwarf elder (Bot.), danewort.

   Dwarf wall (Arch.), a low wall, not as high as the story of
      a building, often used as a garden wall or fence. --Gwilt.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Elder \El"der\, n. [OE. ellern, eller, AS. ellen, cf. LG.
   elloorn; perh. akin to OHG. holantar, holuntar, G. holunder;
   or perh. to E. alder, n.] (Bot.)
   A genus of shrubs (Sambucus) having broad umbels of white
   flowers, and small black or red berries.
   [1913 Webster]

   Note: The common North American species is Sambucus
         Canadensis; the common European species (S. nigra)
         forms a small tree. The red-berried elder is S.
         pubens. The berries are diaphoretic and aperient. The
         European elder (Sambucus nigra) is also called the
         elderberry, bourtree, Old World elder, black
         elder, and common elder.
         [1913 Webster + WordNet 1.5]

   Box elder. See under 1st Box.

   Dwarf elder. See Danewort.

   Elder tree. (Bot.) Same as Elder. --Shak.

   Marsh elder, the cranberry tree Viburnum Opulus).
      [1913 Webster]

WordNet (r) 3.0 (2006):

dwarf elder
    n 1: dwarf herbaceous elder of Europe having pink flowers and a
         nauseous odor [syn: dwarf elder, danewort, Sambucus
         ebulus]
    2: bristly herb of eastern and central North America having
       black fruit and medicinal bark [syn: bristly sarsaparilla,
       bristly sarsparilla, dwarf elder, Aralia hispida]