cur·va·ture (kûrvə-chr′, -chər)
1. The act of curving or the state of being curved.
a. The ratio of the change in the angle of a tangent that moves over a given arc to the length of the arc.
b. The limit of this ratio as the length of the arc approaches zero.
c. The reciprocal of the radius of a circle.
3. Medicine A curving or bending, especially an abnormal one: curvature of the spine.
[Middle English, from Latin curvātūra, from curvātus, past participle of curvāre, to bend, from curvus, curved; see sker-2 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.