1. constant in effort to accomplish something; attentive and persistent in doing anything: a diligent student.
  2. done or pursued with persevering attention; painstaking: a diligent search of the files.

Origin of diligent

1300–50; Middle English (< Anglo-French) < Latin dīligent- (stem of dīligēns), present participle of dīligere to choose, like, equivalent to dī- di-2 + -ligere (combining form of legere to choose, read); see -ent
Related formsdil·i·gent·ly, adverbdil·i·gent·ness, nounnon·dil·i·gent, adjectivenon·dil·i·gent·ly, adverbo·ver·dil·i·gent, adjectiveo·ver·dil·i·gent·ly, adverbo·ver·dil·i·gent·ness, nounpre·dil·i·gent, adjectivepre·dil·i·gent·ly, adverbun·dil·i·gent, adjectiveun·dil·i·gent·ly, adverb

Synonyms for diligent

Synonym study

1. See busy.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

British Dictionary definitions for undiligent


  1. careful and persevering in carrying out tasks or duties
  2. carried out with care and perseverancediligent work
Derived Formsdiligently, adverb

Word Origin for diligent

C14: from Old French, from Latin dīligere to value, from dis- apart + legere to read
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Word Origin and History for undiligent



mid-14c., from Old French diligent (14c.), from Latin diligentem "attentive, assiduous" (see diligence). Related: Diligently.

Online Etymology Dictionary, © 2010 Douglas Harper