consistent

Etymology

From Latin consistens, present participle of cōnsistō (“to agree with; to continue”), from con- (“prefix indicating a being or bringing together of several objects”) (ultimately from Proto-Indo-European *ḱóm (“beside, by, near, with”)) + sistō (“to cause to stand; to place, set”) (ultimately from Proto-Indo-European *stísteh₂ti (“to be standing up; to be getting up”), from the root *steh₂- (“to stand (up)”)).

adj

1. Of a regularly occurring, dependable nature.
   The consistent use of Chinglish in China can be very annoying, apart from some initial amusement.
   He is very consistent in his political choices: economy good or bad, he always votes Labour!
2. Compatible, accordant.
   Libertarian paternalism is the view that, because the way options are presented to citizens affects what they choose, society should present options in a way that "nudges" our intuitive selves to make choices that are more consistent with what our more deliberative selves would have chosen if they were in control. 2012 January, Steven Sloman, “The Battle between Intuition and Deliberation [review of Thinking, Fast and Slow (2011) by Daniel Kahneman]”, in American Scientist, volume 100, number 1, archived from the original on 2012-01-08, page 74
3. (logic) Of a set of statements: such that no contradiction logically follows from them.
   When we ask whether ideas or terms are consistent or inconsistent with each other, the question really is, in what manner the relation presupposed between the ideas qualifies them for being combined as terms of a judgment. 1857, William Spalding, “Introduction”, in An Introduction to Logical Science: Being a Reprint of the Article “Logic” from the Eighth Edition of the Encyclopædia Britannica, Edinburgh: Adam and Charles Black, chapter II (The Function and Axioms of Logical Science), paragraph 12(2), pages 22–23
   Part of establishing a foundation for geometry was demonstrating that the axioms were consistent – that they could never lead to contradictions. 2008, Charles Petzold, “Centuries of Progress”, in The Annotated Turing: A Guided Tour through Alan Turing’s Historic Paper on Computability and the Turing Machine, Indianapolis, Ind.: Wiley Publishing, page 39

noun

1. (in the plural, rare) Objects or facts that are coexistent, or in agreement with one another.
   The Diurnal motion of the primum mobile, is it not from Eaſt to Weſt? And the annual motion of the Sun through the Ecliptick, is it not on the contrary from Weſt to Eaſt? How then can you make theſe motions being conferred on the Earth, of contraries to become conſiſtents? 1661, Galileo Galilei, “Galilæus: Galilæus Lincæus, His Systeme of the World. The Second Dialogue.”, in Thomas Salusbury, transl., Mathematical Collections and Translations, volume I, part I, London: William Leybourne, →OCLC, pages 234–235
2. (Eastern Orthodoxy, historical) A kind of penitent who was allowed to assist at prayers, but was not permitted to receive the holy sacraments.