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alethic

British  
/ əˈliːθɪk /

adjective

  1. logic

    1. of or relating to such philosophical concepts as truth, necessity, possibility, contingency, etc

    2. designating the branch of modal logic that deals with the formalization of these concepts

"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

Etymology

Origin of alethic

C20: from Greek alētheia truth