D defs.my
Entry 2 senses Webster, 1913

Diligent

/dĭl'-ĭj-ənt/ · Dil·i·gent · IPA /ˈdɪlɪdʒənt/
01 a. Prosecuted with careful attention and effort; careful; painstaking; not careless or negligent.
  1. 1.
    Prosecuted with careful attention and effort; careful; painstaking; not careless or negligent.
    “The judges shall make diligent inquisition.” — Deut. xix. 18.
  2. 2.
    Interestedly and perseveringly attentive; steady and earnest in application to a subject or pursuit; assiduous; industrious.
    “Seest thou a man diligent in his business? he shall stand before kings.” — Prov. xxii. 29.
    Diligent cultivation of elegant literature.” Prescott.