allegory vs Magen David

allegory and Magen David both are nouns.

Word	Noun	Adjective	Verb	Adverb
allegory	Yes	No	No	No
Magen David	Yes	No	No	No

As nouns, Magen David is a hyponym of allegory; that is, Magen David is a word with a more specific, narrower meaning than allegory:

allegory: a visible symbol representing an abstract idea
Magen David: a six-pointed star formed from two equilateral triangles; an emblem symbolizing Judaism

allegory (noun)	Magen David (noun)
a short moral story (often with animal characters)	a six-pointed star formed from two equilateral triangles; an emblem symbolizing Judaism
an expressive style that uses fictional characters and events to describe some subject by suggestive resemblances; an extended metaphor
a visible symbol representing an abstract idea