logic

noun

log·​ic ˈlä-jik How to pronounce logic (audio)
Synonyms of logicnext
1
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
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
logician noun

Did you know?

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 a wet umbrella, 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
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Terafab is designed to produce up to one trillion watts of compute annually, integrating logic, memory, and advanced packaging in a single facility. Jijo Malayil, Interesting Engineering, 22 Mar. 2026 But that same logic was applied to other things like weakening labor protections, with factories shutting down and the country beginning to see the demise of labor unions. John Blake, CNN Money, 22 Mar. 2026 The materiality, in combination with the pragmatic storage solutions, recalls the logic of boat design, where every inch is studied and nothing is left to chance. Ludovica Stevan, Architectural Digest, 22 Mar. 2026 Tiisetso’s view South Africa’s competition regime is built around the view that more operators automatically mean better outcomes for consumers, a logic that made sense in the early mobile era, Mupita said. Tiisetso Motsoeneng, semafor.com, 20 Mar. 2026 See All Example Sentences for logic

Word History

Etymology

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, in the meaning defined at sense 1a(1)

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

Browse Nearby Words

Cite this Entry

“Logic.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/logic. Accessed 26 Mar. 2026.

Kids Definition

logic

noun
log·​ic ˈläj-ik How to pronounce logic (audio)
1
: the study of the rules and tests of sound reasoning
2
: reasoning sense 1
especially : sound reasoning
no logic in that remark
3
: connection (as of facts or events) in a way that seems reasonable
the logic of a situation
4
: the arrangement of circuit elements (as in a computer) needed for computation

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