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I was wondering if there are differences between the cases of using di- and the cases of using bi-?

For example,

  • why carbon dioxide instead of carbon bioxide?
  • Why binoculars instead of dinoculars?
  • Why bisexual instead of disexual?
  • Why bilateral instead of dilateral?
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Almost 2k points and you're still saying "thanks" in a post? –  simchona Feb 9 '12 at 21:15
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Don't say "thanks" in a post. It's spam. –  simchona Feb 9 '12 at 21:16
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@MattЭллен: What if I don't buy that? –  Tim Feb 9 '12 at 21:55

1 Answer 1

up vote 10 down vote accepted

Bi- comes from Latin, Di- from Greek. Which prefix is used would usually depend on the origin of the root of the word.

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Thanks! Seems like I have to learn history of each such word! Possibly any rule saying that which is used more often in what category? For example, in chemistry, di-; in social science and physics, bi-? –  Tim Feb 9 '12 at 21:18
    
Precisely. Dioxide is a Greek word, whereas binoculars and bisexual are of Latin origin. +1. –  Irene Feb 9 '12 at 21:20
    
You could learn the history ... or you could just accept whatever you find in the dictionary. While it is sometimes useful to know the origins of a word, 95% of the time you can just use it without having to know that it came from Latin via French or that it was coined by Hiram Slocum in 1892 or whatever. –  Jay Feb 9 '12 at 22:02
    
Plenty of Latin words have the prefix di- or dis- thought they often lose the sense of 2 by the time they arrive in English: compare bisection and dissection. –  Henry Feb 9 '12 at 22:51
    
@Henry: In mathematics, is bi- more often than di-? I cannot think of some examples with di-. –  Tim Feb 9 '12 at 23:11

protected by RegDwigнt Mar 14 '13 at 11:58

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