The English abbreviation Ph.D. comes from the Latin for Doctor of Philosophy, which I understand would be either Philosophiae Doctor or Doctor Philosophiae.
I know word order is flexible in Latin, but I thought that the general rule was "noun + modifier." If so, Doctor Philosophiae would be the preferred form. And yet the widespread usage of Ph.D. suggests that the opposite order, Philosophiae Doctor, prevailed. Is there a grammatical reason that the latter option became the source of the Ph.D. abbreviation?
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