[ rash-ee-os-uh-neyt, -oh-suh-, rat-ee- ]
/ ˌræʃ iˈɒs əˌneɪt, -ˈoʊ sə-, ˌræt i- /

verb (used without object), ra·ti·oc·i·nat·ed, ra·ti·oc·i·nat·ing.

to reason; carry on a process of reasoning.

Nearby words

  1. ratingen,
  2. ratiné,
  3. ratio,
  4. ratio scale,
  5. ratio test,
  6. ratiocination,
  7. ratiometer,
  8. ration,
  9. rational,
  10. rational form

Origin of ratiocinate

1635–45; < Latin ratiōcinātus past participle of ratiōcinārī to reckon, calculate, conclude, verbal derivative of ratiō reason

Related formsra·ti·oc·i·na·tor, noun

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for ratiocinate

British Dictionary definitions for ratiocinate


/ (ˌrætɪˈɒsɪˌneɪt) /


(intr) to think or argue logically and methodically; reason
Derived Formsratiocination, nounratiocinative, adjectiveratiocinator, noun

Word Origin for ratiocinate

C17: from Latin ratiōcinārī to calculate, from ratiō reason

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 ratiocinate



"to reason," 1640s, from Latin ratiocinatus, past participle of ratiocinare (see ratiocination). Related: Ratiocinant.

Online Etymology Dictionary, © 2010 Douglas Harper