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?

Related question on ELU.SE: Why PhD, and not DPh

  • I was always under the impression that it was Philosophical Doctor, not Doctor of Philosophy (which, though it makes little sense in English, might be fine in Latin)
    – Nic
    Feb 24 '16 at 0:11
  • 1
    In the German-speaking countries, the usual form is Dr. phil. (and Dr. med., Dr. iur. etc.).
    – chirlu
    Feb 24 '16 at 1:16
  • 3
    Isn't this question about English rather than Latin? As far as I know, Ph.D. is an English phrase, not a Latin phrase. It's based on Latin words, but these words were assembled to fit English speakers, not by Latin speakers. Feb 24 '16 at 1:29
  • 1
    @Gilles I see it as a Latin word order question that later has an impact on English. Why does "Philosophiae Doctor" exist in the first place? There's nothing "more English" about Ph.D. than D.Ph. or D.P., so where did it come from? Feb 24 '16 at 2:01
  • 1
    @Nathaniel I'll keep looking for the exact dates these came into being. Also, note that in Oxford and other places, M.Phil. and D.Phil. are standard, not unlike the German abbreviation.
    – cmw
    Feb 29 '16 at 21:18

There is no significance to the word order, and both are perfectly acceptable in Latin. In fact, it is only in English translation that there is a difference felt. The genitive in Latin is perfectly at home come before or after the noun. For example, Lucretius wrote De Rerum Natura while Cicero wrote De Natura Deorum. The choice is stylistic.

And Ph.D. isn't so standard after all. While it's the most popular abbreviation in the American system, in the UK you can get a D.Phil. in Oxford, and in Germany the abbreviation begins with Dr.

So there's no grammatical reason for adopting one or the other.


"Philosophiae" is not a modifier, but a noun in the genitive case, so the assumption behind the question is faulty.

  • 7
    It is indeed a genitive noun, but it's also acting as a modifier (modifying doctor).
    – Draconis
    Jul 9 '21 at 23:19

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.