coherence

American  

[koh-heer-uhns, -her-] / koʊˈhɪər əns, -ˈhɛr- /

Also coherency

noun

1. the act or state of cohering; cohesion.

2. logical interconnection; overall sense or understandability.

3. congruity; consistency.

   Synonyms:

   rationality, agreement, harmony, correspondence

4. Physics, Optics. (of waves) the state of being coherent.

5. Linguistics. the property of unity in a written text or a segment of spoken discourse that stems from the links among its underlying ideas and from the logical organization and development of its thematic content.

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coherence British  

/ kəʊˈhɪərənsɪ, kəʊˈhɪərəns /

noun

1. logical or natural connection or consistency

2. another word for cohesion

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coherence Scientific  

/ kō-hîr′əns,-hĕr′- /

1. A property holding for two or more waves or fields when each individual wave or field is in phase with every other one. Lasers, for example, emit almost perfectly coherent light; all the photons emitted by a laser have the same frequency and are in phase. Since quantum states can be described by a wave equation, coherence can hold for quantum states in general, though only among bosons. Coherence is generally possible in physical systems that may undergo superposition. Maintaining coherence of light is important in fiber optic communications.

2. See also Bose-Einstein condensate

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Other Word Forms

• noncoherence noun
• noncoherency noun

Etymology

Origin of coherence

First recorded in 1570–80; coher(ent) + -ence

Explanation

When something has coherence, all of its parts fit together well. An argument with coherence is logical and complete — with plenty of supporting facts. Coherence comes from a Latin word meaning “to stick together." When you say policies, arguments and strategies are coherent, you’re praising them for making sense. Scientists are always looking for coherence in data to support their hypotheses. And coaches are always looking for coherence in their teams, so they don't fall apart.

Example Sentences

"The complication, however, is that the tent may now be so big that there isn't a lot of ideological coherence in it."

From BBC • Apr. 13, 2026

This would mean "joint supervision, harmonised insolvency and greater tax coherence, which go far beyond what is currently proposed", she told AFP.

From Barron's • Mar. 16, 2026

Wright’s English subjects are, like his contemporary Edward Gibbon’s Romans, backlit by a skepticism whose coherence derives from the Enlightenment confidence in objective reason.

From The Wall Street Journal • Mar. 14, 2026

Bowe restores coherence by allowing federal prisoners to return to court when later developments reveal that earlier denials rested on conclusions the Supreme Court has since rejected.

From Slate • Jan. 10, 2026

One trouble with this view is that it attributes to biology and medicine a much greater store of usable information, with coherence and connectedness, than actually exists.

From "The Lives of a Cell" by Lewis Thomas

Related Words

• consistency
• continuity
• integrity
• rationality
• solidarity
• unity