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definitions

mandatory

[man-duh-tawr-ee, -tohr-ee]
adjective
  1. authoritatively ordered; obligatory; compulsory: It is mandatory that all students take two years of math.
  2. pertaining to, of the nature of, or containing a command.
  3. Law. permitting no option; not to be disregarded or modified: a mandatory clause.
  4. having received a mandate, as a nation.
noun, plural man·da·to·ries.
  1. mandatary.

Origin of mandatory

From the Late Latin word mandātōrius, dating back to 1655–65. See mandate, -tory1
Related formsman·da·to·ri·ly, adverbnon·man·da·to·ry, adjective, noun, plural non·man·da·to·ries.un·man·da·to·ry, adjective

Synonyms for mandatory

1. requisite, exigent.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for mandatorily

mandatory

adjective
  1. having the nature or powers of a mandate
  2. obligatory; compulsory
  3. (of a state) having received a mandate over some territory
noun plural -ries
  1. Also called: mandatary a person or state holding a mandate
Derived Formsmandatorily, adverb
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 mandatorily

mandatory

adj.

1570s, "of the nature of a mandate," from Late Latin mandatorius "pertaining to a mandator," from Latin mandatus, past participle of mandare (see mandate (n.)). Sense of "obligatory because commanded" is from 1818.

Online Etymology Dictionary, © 2010 Douglas Harper