[1] : The Collaborative International Dictionary of English v.0.48

indentation \in`denta"tion\, n.
   1. the act of indenting or state of being indented.
      1913 webster

   2. a notch or recess, in the margin or border of anything;
      as, the indentations of a leaf, of the coast, etc.
      1913 webster

   3. a recess or sharp depression in any surface.
      1913 webster

   4. print.
      a the act of beginning a line or series of lines at a
          little distance within the flush line of the column or
          page, as in the common way of beginning the first line
          of a paragraph.
      b the measure of the distance; as, an indentation of one
          em, or of two ems.
          1913 webster

   hanging indentation, or reverse indentation, indentation
      of all the lines of a paragraph except the first, which is
      a full line; also called a hanging indent.
      1913 webster
see also:
hanging indentation reverse indentation hanging indent 

[2] : WordNet (r) 2.0

indentation
     n 1: a concave cut into a surface or edge as in a coastline
          syn: indenture
     2: the formation of small pits in a surface as a consequence of
        corrosion syn: pitting, roughness
     3: the space left between the margin and the start of an
        indented line syn: indent, indenture
     4: the act of cutting into an edge with toothlike notches or
        angular incisions
see also:
indenture pitting roughness indent 

[3] : Moby Thesaurus II by Grady Ward, 1.0

91 moby thesaurus words for "indentation":
   alveolation, alveolus, blaze, boss, bump, cleft, colophon,
   concavity, convexity, crena, cut, dactylogram, dactylograph, dent,
   depression, digging, dimple, dint, embossment, engraving,
   excavation, excrescence, feel, fingerprint, finish, footmark,
   footprint, footstep, fossil footprint, furrow, gash, gouge, grain,
   granular texture, hack, hollow, honeycomb, ichnite, ichnolite,
   impress, impression, imprint, incision, indent, indention,
   indenture, jag, jog, joggle, kerf, knub, lump, mark, mining, nap,
   nick, nock, notch, nub, pad, paw print, pawmark, pile, pimple, pit,
   pock, pockmark, print, protuberance, pug, pugmark, score, scotch,
   seal, shag, sigil, signet, stamp, step, structure, stud,
   sunken part, surface, surface texture, texture, thumbmark,
   thumbprint, vestige, wale, weave, woof

Indentation >> I Words
Indentation, definition of term: Indentation
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