anti- or ant-
a. Opposite: antimere.
b. Opposing; against: antiapartheid.
c. Counteracting; neutralizing: antacid.
d. Destroying: antiaircraft.
a. Inverse: antilogarithm.
b. Displaying opposite characteristics: antihero.
[Greek, from anti, opposite; see ant- in the Appendix of Indo-European roots.]
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Indo-European & Semitic Roots Appendices
Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:
The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.