from The American Heritage® Dictionary of the English Language, 4th Edition
- Two; twice; double: dichromatic.
- Containing two atoms, radicals, or groups: dichloride.
- Variant of dia-.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- Meaning two, twice, or double.
- An occasionally used form of dis-.
- A form of dia- before a vowel.
from the GNU version of the Collaborative International Dictionary of English
- A prefix, signifying twofold, double, twice.
Greek; see dwo- in Indo-European roots.(American Heritage® Dictionary of the English Language, Fourth Edition)
From Ancient Greek δίς (dis, "twice"). (Wiktionary)
From Ancient Greek δία (dia, "through"). (Wiktionary)