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vig·i·lant

(vĭjə-lənt)

adj.

On the alert, as for danger or error; watchful. See Synonyms at careful.

[Middle English, from Old French, from Latin vigilāns, vigilant-, present participle of vigilāre, to be watchful; see VIGILANTE.]

vigi·lant·ly adv.

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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