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as·sid·u·ous

(ə-sĭj-əs)

adj.

Showing or characterized by persistent attention or untiring application: an assiduous worker who strove for perfection; did assiduous research before writing the book. See Synonyms at diligent.

[From Latin assiduus, from assidēre, to attend to : ad-, ad- + sedēre, to sit; see sed- in the Appendix of Indo-European roots.]

as·sidu·ous·ly adv.

as·sidu·ous·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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