Definition: 7.12: Coprime (Relatively Prime) Numbers
(Definition 12 from Book 7 of Euclid's “Elements”)
Numbers prime to one another are those (which are) measured by a unit alone as a common measure.
Modern Formulation
see coprimality.
Mentioned in:
Proofs: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32
Propositions: 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51
Thank you to the contributors under CC BYSA 4.0!
 Github:

 nonGithub:
 @Fitzpatrick
References
Bibliography
 Landau, Edmund: "Vorlesungen über Zahlentheorie, Aus der Elementaren Zahlentheorie", S. Hirzel, Leipzig, 1927
Adapted from (subject to copyright, with kind permission)
 Fitzpatrick, Richard: Euclid's "Elements of Geometry"