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definitions

gratuitous

[gruh-too-i-tuhs, -tyoo-]
adjective
  1. given, done, bestowed, or obtained without charge or payment; free; voluntary.
  2. being without apparent reason, cause, or justification: a gratuitous insult.
  3. Law. given without receiving any return value.

Origin of gratuitous

1650–60; < Latin grātuītus free, freely given, spontaneous, derivative of grātus thankful, received with thanks (for formation cf. fortuitous); see -ous
Related formsgra·tu·i·tous·ly, adverbgra·tu·i·tous·ness, nounnon·gra·tu·i·tous, adjectivenon·gra·tu·i·tous·ly, adverbnon·gra·tu·i·tous·ness, nounun·gra·tu·i·tous, adjectiveun·gra·tu·i·tous·ly, adverbun·gra·tu·i·tous·ness, noun
Can be confusedgracious gratis gratuitous

Synonyms for gratuitous

2. unnecessary, superfluous, redundant; causeless, unreasonable, groundless, unprovoked, unjustified.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for non-gratuitous

gratuitous

adjective
  1. given or received without payment or obligation
  2. without cause; unjustified
  3. law given or made without receiving any value in returna gratuitous agreement
Derived Formsgratuitously, adverbgratuitousness, noun

Word Origin for gratuitous

C17: from Latin grātuītus, from grātia favour
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 non-gratuitous

gratuitous

adj.

1650s, "freely bestowed," from Latin gratuitus "done without pay, spontaneous, voluntary," from gratus "pleasing, agreeable," from gratia "favor" (see grace). Sense of "uncalled for, done without good reason" is first recorded 1690s.

Online Etymology Dictionary, © 2010 Douglas Harper