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diligent vs. vigilant

[dil-i-juhnt] / ˈdɪl ɪ dʒənt /

adjective

  1. constant in effort to accomplish something; attentive and persistent in doing anything.

    a diligent student.

    Synonyms:
    sedulous, assiduous, industrious
  2. done or pursued with persevering attention; painstaking.

    a diligent search of the files.

    Synonyms:
    unremitting, tireless, indefatigable
[vij-uh-luhnt] / ˈvɪdʒ ə lənt /

adjective

  1. keenly watchful to detect danger; wary.

    a vigilant sentry.

    Antonyms:
    careless
  2. ever awake and alert; sleeplessly watchful.

    Synonyms:
    sleepless, wide-awake