Recently I tried to define what The Star of David is not. Today I'll try to define what it is:
The Star of David has a shape, a meaning and a name:
1. Meaning: The Star of David is a symbol, an emblem, a logo of Judaism and Zionism.
2. Shape: The Star of David is a shape, a hexagram, a six-pointed star formed by two equilateral triangles which have the same center and are placed in opposite directions. It can be: (a) two dimensional or (b) three dimensional like perforation, or engraving or (c) three dimensional created by two interlocking tetrahedrons.
3. Name: The Star of David is the Shield of David, which refers to the Lord, who is also the Shield of Abram. The same name serves both the Jewish and the Christian Stars of David and there's a need for disambiguation.
4. Product: The Star of David is a product in the shape of a six-pointed star, such as necklace, earring, lampshade etc.
Trying to define the Star of David by its shape alone is not enough - even though the Star of David is a hexagram not every hexagram is a Star of David. This is a source of confusion for many people who see it on Indian temples, or as sheriffs' badges, or as Chinese checkers etc.
Trying to define it by the name alone is not enough since it has other meanings that are not necessarily connected to the shape.
Trying to define it as a product alone is not enough since there are non- Jewish products in the same shape.
So my definition is: The Star of David is the name of a two or three dimensional six-pointed star which is the emblem of Judaism and Zionism.