Euclidean Fifth Postulate

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When did Euclidean Fifth Postulate comes to be called the Parallel Postulate? It is taken for granted. Did Euclid refer to the fifth postulate as the Parallel Postulate?

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The fifth postulate does not specifically talk about parallel lines, it is only a postulate related to parallelism. Euclid gave the definition of parallel lines in Book I, Definition 23 just before the five postulates. However, we see that there is the following equivalence:

Equivalence to the Euclidean Parallel Postulate

About the history of the fifth postulate see the article

History of the Parallel Postulate by Florence P. Lewis.