inconsistent

[in-kuhn-sis-tuhnt]

adjective

1. lacking in harmony between the different parts or elements; self-contradictory.

   an inconsistent story.

   Synonyms: incoherent

2. lacking agreement, as one thing with another or two or more things in relation to each other; at variance.

   a summary that is inconsistent with the previously stated facts.

   Synonyms: irreconcilable, discrepant

3. not consistent in principles, conduct, etc..

   He's so inconsistent we never know if he'll be kind or cruel.

4. acting at variance with professed principles.

5. Logic.,  incompatible.

inconsistent

/ ˌɪnkənˈsɪstənt /

adjective

1. lacking in consistency, agreement, or compatibility; at variance

2. containing contradictory elements

3. irregular or fickle in behaviour or mood

4. Also: incompatible. maths (of two or more equations) not having one common set of values of the variables: x + 2 y = 5 and x + 2 y = 6 are inconsistent

5. logic (of a set of propositions) enabling an explicit contradiction to be validly derived

Other Word Forms

• inconsistently adverb

Word History and Origins

Origin of inconsistent¹

First recorded in 1640–50; in- ³ + consistent

Synonym Study

Inconsistent, incompatible, incongruous refer to things that are out of keeping with each other. That which is inconsistent involves variance, discrepancy, or even contradiction, especially from the point of view of truth, reason, or logic: His actions are inconsistent with his statements. Incompatible implies incapability of close association or harmonious relationship, as from differences of nature, character, temperament, and the like: actions incompatible with honesty of purpose; qualities that make two people incompatible. Something that is incongruous is inappropriate or out of keeping, often to the point of being ridiculous or absurd: Incongruous characters or situations frequently provide a basis for comedy.

Example Sentences

But less than two months later, it announced that Lean Screen would be recalled after it returned inconsistent results across eight different sets of lab testing.

From BBC

Instead, his fastball is still lacking life, his performances remain inconsistent, and his plan for the rest of this season is up in the air.

From Los Angeles Times

The commission concluded that an analysis of the betting data was not "illustrative of a spot-fix" and added it was "in many respects inconsistent with a spot-fix, but consistent with alternative explanations".

From BBC

They’ve been inconsistent, struggling to stack clean performances or any semblance of an extended winning streak.

From Los Angeles Times

The company described the notes in the document, obtained by Reuters, as erroneous and inconsistent with its policies which prohibit any content sexualising children.

From BBC

Related Words

• conflicting 
• contrary 
• erratic 
• illogical 
• incompatible 
• irreconcilable 
• uncertain 
• unpredictable