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de·on·tol·o·gy

(dē′ŏn-tŏlə-jē)

n. pl. de·on·tol·o·gies

1. Ethical or moral theory concerned with duties and rights.

2. The doctrine that ethical status of an action lies in its adherence to a set of rules.

[Greek deon, deont-, obligation, necessity (from neuter present participle of dein, to need, lack; see deu-¹ in the Appendix of Indo-European roots) + -LOGY.]

de·on′to·logi·cal (-tə-lŏjĭ-kəl) adj.

de·on′to·logi·cal·ly adv.

de′on·tolo·gist n.

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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