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no·ce·bo

(nō-sēbō)

n. pl. no·ce·bos or no·ce·boes

A substance that causes undesirable side effects as a result of a patient's perception that it is harmful rather than as a result of a causative ingredient.

[Latin nocēbō, I will harm, first person sing. future tense of nocēre, to harm (on the model of PLACEBO); see nek-¹ in the Appendix of Indo-European roots.]

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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