# disloyalty

/dɪˈsɫɔɪəɫti/ (US) · /dɪslˈɔɪəlti/ (UK) · CEFR B2 · Noun

Source: https://englishreference.com/word/disloyalty
Updated: 2026-10-18

## Definition

a lack of support or faithfulness toward someone you should stay loyal to, like a friend, partner, or country. You show it when you break trust or help the other side.

For teachers: failure to remain faithful or supportive toward a person, group, or cause to which allegiance is owed. Often contrasted with loyalty in discussions of personal relationships, employment, or politics.

## Examples

- His friends see his lies as disloyalty.
- The manager treats sharing company secrets with rivals as serious disloyalty.
- Historians still debate whether his negotiations with the enemy amounted to treason or merely political disloyalty born of desperation.

## Synonyms

betrayal, treachery, infidelity, treason, unfaithfulness

## Antonyms

loyalty, faithfulness, fidelity, allegiance

## Usage notes

- Often followed by 'to' or 'toward' to name the person or group betrayed, as in 'disloyalty to friends'.

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From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.