log·​ic | \ ˈlä-jik How to pronounce logic (audio) \

Essential Meaning of logic

1 : a proper or reasonable way of thinking about or understanding something If you just use a little logic, you'll see I'm right. the rules of logic See More ExamplesThere's no logic in/to your reasoning. I can't see the logic in always worrying about the future. = Where's the logic in always worrying about the future? There's some logic to/in what he says. She kept the dog, against all logic, after it attacked her. [=her decision to keep the dog was not logical/sensible] Her decision defies logic. [=her decision makes no sense; her decision is not logical] There's a certain logic in/to what he says.Hide
2 : a particular way of thinking about something I could not understand her logic in keeping the dog. [=I could not understand her reason for keeping the dog] I fail to see your logic. = I fail to see the logic behind/of your reasoning. faulty logic
3 : the science that studies the formal processes used in thinking and reasoning a professor of logic

Full Definition of logic

1a(1) : a science that deals with the principles and criteria of validity of inference and demonstration : the science of the formal principles of reasoning a professor of logic
(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 the logic of grammar
b(1) : a particular mode of reasoning viewed as valid or faulty She spent a long time explaining the situation, but he failed to see her logic.
(2) : relevance, propriety could not understand the logic of such an action
c : interrelation or sequence of facts or events when seen as inevitable or predictable By the logic of events, anarchy leads to dictatorship.
d : the arrangement of circuit elements (as in a computer) needed for computation also : the circuits themselves
2 : something that forces a decision apart from or in opposition to reason the logic of war

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Other Words from logic

logician \ lō-​ˈji-​shən How to pronounce logic (audio) \ noun

How are logistics and logic related?

Logistics follows the same pattern of other plural nouns—such as ballistics, linguistics, statistics, or physics—that represent fields of study and take either a singular or plural verb.

Logic, used strictly in the singular, is a science that deals with the formal principles of reason. If a visitor walks in the house with wet hair, it is logical for one to assume that it is raining outside. Logistics, which involves such concerns as the delivery of personnel or supplies in an efficient manner, can often employ logic, such as by reasoning out the path least likely to interrupt the flow of a delivery:

As with many other areas of the economy, the digital revolution is having a profound effect on delivery logistics. The combination of mobile computing, analytics, and cloud services, all of which are fueled by the Internet of Things (IoT), is changing how delivery and fulfillment companies are conducting their operations.
—Andrew Meola, Business Insider, 14 Oct. 2016

Both logic and logistics ultimately derive from the Greek logos, meaning "reason." But while logic derives directly from Greek, logistics took a longer route, first passing into French as logistique, meaning "art of calculating," and then into English from there.

Examples of logic in a Sentence

If you just use a little logic, you'll see I'm right. There's no logic in your reasoning. There's some logic to what he says. There's a certain logic in what he says. The revolution proceeded according to its own logic. the logic of the situation
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Recent Examples on the Web Apply this same logic to San Francisco’s recall of Boudin. Justin Phillips, San Francisco Chronicle, 26 Sep. 2021 The same logic applies to areas like racial diversity where, again, science lags the wider economy by some margin. Kath Mackay, Forbes, 20 Sep. 2021 That inspired Wooller to think about applying the same logic to something bigger—a whole mammoth tusk—to investigate an aspect of mammoth ecology that isn’t well-understood. Riley Black, Smithsonian Magazine, 12 Aug. 2021 Probably not, and the same logic goes for financial advice. cleveland, 7 Aug. 2021 Arizona in November will presumably look better, more competent than Arizona in September, but that same logic applies to a Utah team expected to challenge for the Pac-12 South. Josh Newman, The Salt Lake Tribune, 10 July 2021 Democrats, succumbing to the same neoliberal logic, began treating all tax increases as a quick ticket to electoral disaster, and bought into Republicans’ core conceit even as deficits grew. Jacob Silverman, The New Republic, 18 June 2021 The same logic applies when a significant number of vehicles are EVs. Star Tribune, 11 June 2021 This same logic applies to washing dishes, running the dishwasher, or doing laundry. Janelle James, Detroit Free Press, 10 June 2021

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'logic.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of logic

12th century, in the meaning defined at sense 1a(1)

History and Etymology for 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

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Time Traveler for logic

Time Traveler

The first known use of logic was in the 12th century

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Dictionary Entries Near logic

log glass



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Statistics for logic

Last Updated

9 Oct 2021

Cite this Entry

“Logic.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/logic. Accessed 18 Oct. 2021.

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More Definitions for logic


log·​ic | \ ˈlä-jik How to pronounce logic (audio) \

Kids Definition of logic

1 : a proper or reasonable way of thinking about something : sound reasoning
2 : a science that deals with the rules and processes used in sound thinking and reasoning

More from Merriam-Webster on logic

Nglish: Translation of logic for Spanish Speakers

Britannica English: Translation of logic for Arabic Speakers

Britannica.com: Encyclopedia article about logic


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