Is the prefix "di-" more Latin-like than "bi-"?

Question

Question.

(1) Is there anything close to scientifically-meaningful to say about whether the prefix "di-" is more Latin than the prefix "bi-", when indicating two-ness?

(2) Are there published scholarly references on precisely this question, comparing the two prefixes?

(3) Are there notable Latin words which simultaneously contain "bi" and "di"?

Remarks.

• In a vague sense that I have no time or experience enough to substantiate, this seems to be the case, "di-" seeming significantly more Latin-ish than "bi-" which seems more Greek-ish.

EDIT: like kindly pointed out by the responders, here this attribution of bi to Greek and di to Latin was an accidental mix-up. It is the other way round: bi is Latin, di is Greek.

• Of course, the difference is not clear-cut, there is organic growth and randomness involved, and e.g. in Greek both "bi-" and "di-" appear in composites.

• Both "bi-" and "di-" appear in countless scientific terms.

Answer 1

di- is Greek and bi- is Latin

The Proto-Indo-European root for "two" is reconstructed as *dw-. The remnants of this w can be seen in English "two", Russian dva, Ancient Greek δύο, and many other languages, as well as Latin duo, "two".

Old Latin had many words starting with dv- (where v was pronounced as English "w"). But at some point before Classical times, dv- changed into b- at the beginning of words. Hence dvellum (whence English "duel") became bellum "war", and dvonos became bonus "good".

The word duo "two" itself had a vowel u rather than a consonant v, so it avoided the change. But the prefix dvi- was affected by the change, and became bi-. A similar thing happened in Ancient Greek, which lost the w sound entirely, giving δι-.

So strictly speaking, di- should be used only on Greek roots, and bi- on Latin. But in practice Greek and Latin are mixed together all over the place and the prefix is generally chosen based on what sounds better.

(Compare also the prefixes semi- from Latin and hemi- from Greek, which are sometimes even combined, as in the musical term "hemidemisemiquaver". They're also cognates; s- before vowels at the beginning of words changed into h- in Greek.)

(ETA: Joonas suggested an even clearer pair of cognates, Latin super- and Greek hyper-. Many thanks.)

Answer 2

Your are confused; bi- is Latin and di- is Greek. There is no real difference in meaning between them, but in usage bi- is used with Latin constructions like bisexual and di- with Greek constructions like diglossia. bi- is not a Greek prefix.

(As an aside, I should mention that both Latin bi- and Greek δι‐ have a common origin in a reconstructed ancestor *dwi- .)