incompatible

incompatible — adjective

1. If two people, things, or ways of doing something are incompatible, they are so

1.adjectiveB2
Definition

If two people, things, or ways of doing something are incompatible, they are so different in their basic nature that they cannot work together, stay together, or be used together successfully.

Example

After three years together, Anjali and Erik realised they were fundamentally incompatible.

incompatible + subject (people) — relationship failure

The new printer is incompatible with Walid's old laptop, so he cannot connect them.

incompatible with [device/technology] — hardware mismatch

Common collocations
  • fundamentally incompatible
  • totally incompatible
  • completely incompatible
  • mutually incompatible
  • incompatible with
  • incompatible views
  • incompatible systems
Synonyms
  • conflicting

    Focuses on opposition between ideas, aims, or interests; less common for people or technology

  • mismatched

    Describes things or people that do not go well together; slightly less formal than incompatible

  • contradictory

    Specifically for statements, facts, or ideas that cannot both be true; not used for people or devices

  • clashing

    More informal, often for colours, styles, opinions, or personalities that conflict openly

Antonyms
  • compatible

    Direct opposite — able to exist or work together without conflict

  • harmonious

    Emphasises smooth, peaceful coexistence, typically for relationships or colours

Grammar Patterns

be + incompatible + (with + entity)

be + fundamentally/totally/completely + incompatible

Usage Note

Often followed by the preposition 'with' to name the other person or thing. The subject can be a plural noun phrase covering both entities (e.g., 'The two designs were incompatible'), or a singular noun with 'with' specifying the counterpart.

Common Mistakes

My phone is incompatible for the charger.
My phone is incompatible with the charger.
the correct preposition is 'with', not 'for'.
The two systems are incompatible each other.
The two systems are incompatible with each other.
'with' is required before 'each other'.

Word family

Synonym discussion

Sense: adjective/1

All four words describe a lack of agreement or harmony between two or more things, but they differ in scope and connotation. 'Incompatible' is the broadest — it covers people (personalities), technology (devices), ideas, and facts; it suggests a fundamental difference that prevents successful coexistence. 'Conflicting' is narrower, focusing on opposition between aims, interests, schedules, or evidence, without the same suggestion of deep nature. 'Contradictory' is the most precise for logic and facts: two statements that cannot both be true. 'Mismatched' is more concrete and everyday, often applied to pairs (clothes, couples, furniture) that look odd together but may still function. For example: 'The couple were incompatible and separated' (fundamental); 'The test results gave conflicting information' (opposing); 'His two statements were contradictory' (cannot both be true); 'The socks were mismatched — one blue, one green' (visual mismatch).

incompatible ↗conflictingcontradictory ↗mismatched ↗

Common collocations

Nouns

  • views
  • systems
  • personalities
  • policies
  • interests

Adverbs

Phrases

  • incompatible with each other
  • incompatible by nature

Prepositions

Etymology

LatinFrenchEnglish

The word 'incompatible' comes from the Latin prefix 'in-' meaning 'not' combined with 'compatibilis', from 'compatī' (to sympathise, to suffer with). 'Compatī' is made up of 'com-' (together) and 'patī' (to suffer, to endure). The word entered English through French in the late 16th century, originally used to describe people whose temperaments could not endure each other, and later extended to ideas, systems, and technology.