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allegory vs. metaphor

allegory

[al-uh-gawr-ee, -gohr-ee] / ˈæl əˌgɔr i, -ˌgoʊr i /

noun

plural

allegories

a representation of an abstract or spiritual meaning through concrete or material forms; figurative treatment of one subject under the guise of another.
a symbolical narrative.

the allegory of Piers Plowman.

Synonyms:

parable, fable
emblem.

metaphor

[met-uh-fawr, -fer] / ˈmɛt əˌfɔr, -fər /

noun

a figure of speech in which a term or phrase is applied to something to which it is not literally applicable in order to suggest a resemblance, as in “A mighty fortress is our God.”
something used, or regarded as being used, to represent something else; emblem; symbol.