incompatible

American  

[in-kuhm-pat-uh-buhl] / ˌɪn kəmˈpæt ə bəl /

adjective

1. not compatible; unable to exist together in harmony.

   She asked for a divorce because they were utterly incompatible.

   Synonyms:

   inharmonious, unsuited, unsuitable

2. contrary or opposed in character; discordant.

   incompatible colors.

   Synonyms:

   contradictory, inharmonious

3. that cannot coexist or be conjoined.

4. Logic.

   1. (of two or more propositions) unable to be true simultaneously.

   2. (of two or more attributes of an object) unable to belong to the object simultaneously; inconsistent.

5. (of positions, functions, ranks, etc.) unable to be held simultaneously by one person.

6. Medicine/Medical. of or relating to biological substances that interfere with one another physiologically, as different types of blood in a transfusion.

7. Pharmacology. of or relating to drugs that interfere with one another chemically or physiologically and therefore cannot be mixed or prescribed together.

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noun

1. Usually incompatibles. incompatible persons or things.

2. an incompatible drug or the like.

3. Logic. incompatibles,

   1. two or more propositions that cannot be true simultaneously.

   2. two or more attributes that cannot simultaneously belong to the same object.

incompatible British  

/ ˌɪnkəmˈpætəbəl /

adjective

1. incapable of living or existing together in peace or harmony; conflicting or antagonistic

2. opposed in nature or quality; inconsistent

3. (of an office, position, etc) only able to be held by one person at a time

4. med (esp of two drugs or two types of blood) incapable of being combined or used together; antagonistic

5. logic (of two propositions) unable to be both true at the same time

6. 1. not capable of forming successful grafts

   2. incapable of fertilizing each other

7. maths another word for inconsistent

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noun

1. (often plural) a person or thing that is incompatible with another

Related Words

See inconsistent.

Other Word Forms

• incompatibility noun
• incompatibleness noun
• incompatibly adverb

Etymology

Origin of incompatible

From the Medieval Latin word incompatibilis, dating back to 1555–65. See in- ³, compatible

Example Sentences

"Just as a USB adapter allows devices with different connectors to work together, Floquet magnons could bridge frequencies that would otherwise remain incompatible."

From Science Daily • Mar. 27, 2026

Washington and Tehran have a history of making negotiations happen in the face of seemingly incompatible demands by quietly shelving some of the most contentious points.

From The Wall Street Journal • Mar. 25, 2026

“The UFW has learned of deeply troubling allegations that one of the union’s co-founders, Cesar Chavez, behaved in ways that are incompatible with our organization’s values,” the statement said.

From Salon • Mar. 18, 2026

Jesse and I had great chemistry but were ultimately incompatible.

From Los Angeles Times • Feb. 27, 2026

I can find only two people who, after the publication of Waldseemüller’s map, sought to defend the old theory against its attackers: the new reality was incompatible with the old theories.

From "The Invention of Science" by David Wootton

Related Words

• conflicting
• inappropriate
• incongruous
• inconsistent
• irreconcilable
• unsuitable
• unsuited