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con·sci·en·tious

(kŏn′shē-ĕnshəs)

adj.

1. Guided by or in accordance with the dictates of conscience; principled: a conscientious decision to speak out about injustice.

2. Thorough and assiduous: a conscientious worker; a conscientious effort to comply with the regulations. See Synonyms at diligent.

[Obsolete French conscientieux, from Medieval Latin cōnscientiōsus, from Latin cōnscientia, conscience; see CONSCIENCE.]

con′sci·entious·ly adv.

con′sci·entious·ness 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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