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dis·tur·bance

(dĭ-stûrbəns)

a. The act of disturbing: a disturbance of lake sediments.

b. The condition of being disturbed: “The forest ... is in various stages of disturbance. Only the biggest trees ... have been left standing” (Alex Shoumatoff).

2. Something that disturbs, as a commotion, scuffle, or public tumult.

3. Mental or emotional unbalance or disorder.

4. A variation in normal wind conditions.

5. Geology Folding or faulting that affects a relatively large area.

6. Physics An alteration or displacement of one or more properties of a physical system away from its equilibrium state.

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:

Indo-European Roots

Semitic Roots

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.

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