noun log·ic \ˈlä-jik\

: a proper or reasonable way of thinking about or understanding something

: a particular way of thinking about something

: the science that studies the formal processes used in thinking and reasoning

Full Definition of LOGIC

a (1) :  a science that deals with the principles and criteria of validity of inference and demonstration :  the science of the formal principles of reasoning (2) :  a branch or variety of logic <modal logic> <Boolean logic> (3) :  a branch of semiotics; especially :  syntactics (4) :  the formal principles of a branch of knowledge
b (1) :  a particular mode of reasoning viewed as valid or faulty
(2) :  relevance, propriety
c :  interrelation or sequence of facts or events when seen as inevitable or predictable
d :  the arrangement of circuit elements (as in a computer) needed for computation; also :  the circuits themselves
:  something that forces a decision apart from or in opposition to reason <the logic of war>
lo·gi·cian \lō-ˈji-shən\ noun

Origin of LOGIC

Middle English logik, from Anglo-French, from Latin logica, from Greek logikē, from feminine of logikos of reason, from logos reason — more at legend
First Known Use: 12th century

Other Logic Terms

a posteriori, connotation, corollary, inference, mutually exclusive, paradox, postulate, syllogism
LOGIC Defined for Kids


noun log·ic \ˈlä-jik\

Definition of LOGIC for Kids

:  a proper or reasonable way of thinking about something :  sound reasoning <There's no logic in what you said.>
:  a science that deals with the rules and processes used in sound thinking and reasoning
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