[syn: partition, divider]
4.  a drafting instrument resembling a compass that is used for dividing lines into equal segments or for transferring measurements; 
The Collaborative International Dictionary of English v.0.48:
Divider \Di*vid"er\, n.
   1. One who, or that which, divides; that which separates
      anything into parts.
      [1913 Webster]
   2. One who deals out to each his share.
      [1913 Webster]
            Who made me a judge or a divider over you? --Luke
                                                  xii. 14.
      [1913 Webster]
   3. One who, or that which, causes division.
      [1913 Webster]
            Hate is of all things the mightiest divider.
                                                  --Milton.
      [1913 Webster]
            Money, the great divider of the world. --Swift.
      [1913 Webster]
   4. pl. An instrument for dividing lines, describing circles,
      etc., compasses. See Compasses.
      [1913 Webster]
   Note: The word dividers is usually applied to the instrument
         as made for the use of draughtsmen, etc.; compasses to
         the coarser instrument used by carpenters.
         [1913 Webster]
   5. a vertical structure that divides or separates (as a wall
      divides one room from another).
   Note: The structure may be a wall with an opening in it to
         allow seeing one part of the room from the other. This
         term is also used to designate a semitransparent
         curtain formed by hanging multiple strings of various
         materials from a ceiling, intended to visually
         partition a room without inhibiting passage between the
         partitions
   Syn: partition, room divider.
        [WordNet 1.5 PJC]
WordNet (r) 3.0 (2006):
divider
    n 1: a taxonomist who classifies organisms into many groups on
         the basis of relatively minor characteristics [syn:
         splitter, divider] [ant: lumper]
    2: a person who separates something into parts or groups
    3: a vertical structure that divides or separates (as a wall
       divides one room from another) [syn: partition, divider]
    4: a drafting instrument resembling a compass that is used for
       dividing lines into equal segments or for transferring
       measurements