1. [n]  a section of something that is long and narrow; "a length of timber"; "a length of tubing"
2. [n]  continuance in time; "the ceremony was of short duration"; "he complained about the length of time required"
3. [n]  the linear extent in space from one end to the other; the longest horizontal dimension of something that is fixed in place; "the length of the table was 5 feet"
4. [n]  size of the gap between two places; "the distance from New York to Chicago"; "he determined the length of the shortest line segment joining the two points"
5. [n]  the property of being the extent of something from beginning to end; "the editor limited the length of my article to 500 words"

Length
Children can become mathematical problem solvers, learning to communicate and reason mathematically, by using the Math Counts series. The full-color photographs and simple text encourage talk about topics that are essentially mathematical.

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1. \Length\ (l[e^]ngth), n. [OE. lengthe, AS. leng[eth], fr.
   lang, long, long; akin to D. lengte, Dan. l[ae]ngde, Sw.
   l["a]ngd, Icel. lengd. See {Long}, a. ]
   1. The longest, or longer, dimension of any object, in
      distinction from breadth or width; extent of anything from
      end to end; the longest line which can be drawn through a
      body, parallel to its sides; as, the length of a church,
      or of a ship; the length of a rope or line.
   2. A portion of space or of time considered as measured by
      its length; -- often in the plural.
            Large lengths of seas and shores.     --Shak.
            The future but a length behind the past. --Dryden.
   3. The quality or state of being long, in space or time;
      extent; duration; as, some sea birds are remarkable for
      the length of their wings; he was tired by the length of
      the sermon, and the length of his walk.
   4. A single piece or subdivision of a series, or of a number
      of long pieces which may be connected together; as, a
      length of pipe; a length of fence.
   5. Detail or amplification; unfolding; continuance as, to
      pursue a subject to a great length.
            May Heaven, great monarch, still augment your bliss
            With length of days, and every day like this.
                                                  --Dryden.
   6. Distance.[Obs.]
            He had marched to the length of Exeter. --Clarendon.
   {At length}.
      (a) At or in the full extent; without abbreviation; as,
          let the name be inserted at length.
      (b) At the end or conclusion; after a long period. See
          Syn. of At last, under {Last}.
   {At arm's length}. See under {Arm}.
   

2. \Length\, v. t.
   To lengthen. [Obs.] --Shak.