[1] : The Collaborative International Dictionary of English v.0.48

diligent \dil"igent\, a. f. diligent, l. diligens, -entis, p.
   pr. of diligere, dilectum, to esteem highly, prefer; di- =
   dis- + legere to choose. see legend.
   1. prosecuted with careful attention and effort; careful;
      painstaking; not careless or negligent.
      1913 webster

            the judges shall make diligent inquisition. --deut.
                                                  xix. 18.
      1913 webster

   2. interestedly and perseveringly attentive; steady and
      earnest in application to a subject or pursuit; assiduous;
      industrious.
      1913 webster

            seest thou a man diligent in his business? he shall
            stand before kings.                   --prov. xxii.
                                                  29.
      1913 webster

            diligent cultivation of elegant literature.
                                                  --prescott.

   syn: active; assiduous; sedulous; laborious; persevering;
        attentive; industrious.
        1913 webster
see also:
legend 

[2] : WordNet (r) 2.0

diligent
     adj 1: quietly and steadily persevering especially in detail or
            exactness; "a diligent or patient worker"; "with
            persevering or patient industry she revived the
            failing business" syn: persevering
     2: characterized by care and perseverence in carrying out
        tasks; "a diligent detective investigates all clues"; "a
        diligent search of the files" ant: negligent
see also:
persevering negligent 

[3] : Moby Thesaurus II by Grady Ward, 1.0

129 moby thesaurus words for "diligent":
   academic, advertent, agog, alert, all ears, all eyes, ardent,
   assiduous, attentive, aware, bookish, careful, concentrated,
   conscientious, conscious, constant, continuing, devoted to studies,
   dogged, donnish, dryasdust, earnest, elaborate, enduring,
   energetic, faithful, fervent, finical, finicking, finicky, hard,
   hard-working, hardworking, heedful, immutable, inalterable,
   indefatigable, indomitable, industrious, insistent, intense,
   intent, intentive, invincible, laborious, lasting, loyal, mandarin,
   meticulous, mindful, never idle, never-tiring, nice, niggling,
   observant, observing, obstinate, on the ball, on the job,
   open-eared, open-eyed, openmouthed, operose, owlish, painstaking,
   patient, patient as job, pedantic, permanent, perseverant,
   persevering, persistent, persisting, pertinacious, plodding,
   plugging, preoccupied, professorial, punctilious, rabbinic, rapt,
   regardful, relentless, resolute, scholarly, scholastic, scrupulous,
   sedulous, single-minded, sleepless, slogging, stable, steadfast,
   steady, strenuous, stubborn, studious, tenacious, thorough,
   thoroughgoing, tireless, unabating, unconquerable, undaunted,
   undiscouraged, undrooping, unfailing, unfaltering, unflagging,
   unflinching, unintermitting, uninterrupted, unnodding, unrelaxing,
   unrelenting, unremitting, unsleeping, unsparing, unswerving,
   untiring, unwavering, unwearied, unwearying, unwinking,
   utterly attentive, vehement, watchful, weariless, zealous

Diligent >> D Words
Diligent, definition of term: Diligent
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