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per·turb

(pər-tûrb)

tr.v. per·turbed, per·turb·ing, per·turbs

1. To disturb or confuse; make uneasy or anxious: I was perturbed by his off-color remarks.

a. To cause (a system) to become altered or imbalanced from a normal state: volcanic eruptions that perturbed the climate.

b. Physics & Astronomy To cause perturbation in (the orbit of a celestial body, for example) by gravitational interaction.

[Middle English perturben, from Old French perturber, from Latin perturbāre : per-, per- + turbāre, to throw into disorder (from turba, confusion, perhaps from Greek turbē).]

per·turba·ble adj.

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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