The Collaborative International Dictionary of English v.0.48:

Magen David \Magen David\, n. [Hebrew, shield of David.]
   A hexagram[1a], when used as the symbol of Judaism; called
   also Mogen David and Star of David. It is included on the
   flag of Israel

   Syn: Star of David, Mogen David.
        [PJC]

The Collaborative International Dictionary of English v.0.48:

Mogen David \Mogen David\, n. [Hebrew, shield of David.]
   A hexagram[1a], when used as the symbol of Judaism; called
   also Magen David and Star of David. It is included on the
   flag of the state of Israel

   Syn: Star of David, Magen David.
        [PJC]

The Collaborative International Dictionary of English v.0.48:

Star of David \Star" of Dav"id\
   A symbol consisting of two overlapped equilateral triangles
   forming a star with six points, used as a symbol of Judaism.
   It is also called Magen David, Mogen David, and Shield
   of David, and is shaped identically to the hexagram and
   Solomon's seal. It is used on the flag of the modern state
   of Israel.
   [PJC]

WordNet (r) 3.0 (2006):

Star of David
    n 1: a six-pointed star formed from two equilateral triangles;
         an emblem symbolizing Judaism [syn: Star of David,
         Shield of David, Magen David, Mogen David, Solomon's
         seal]