# ill

/ˈɪɫ/ (US) · /ˈɪl/ (UK)

Source: https://englishreference.com/word/ill
Updated: 2026-07-09

## Senses

### 2. bad or harmful

adjective · CEFR B2 · Formal

bad, harmful, or showing that you do not like someone.

For teachers: harmful, hostile, or unfavorable in nature; often used in fixed expressions regarding intentions or effects.

- I hope you don't have any ill feelings toward me after our argument.
- The sudden closure of the factory had an ill effect on the local economy, leading to a sharp rise in unemployment.

### 3. cool or great

adjective · CEFR C1 · Slang

very good, impressive, or cool.

For teachers: highly impressive or excellent; a reversal of the literal meaning common in urban vernacular.

- That new song has an ill beat.
- The dancer performed an ill sequence of power moves that left the entire audience in shock.

### 4. badly or poorly

adverb · CEFR B2 · Formal

badly or not enough.

For teachers: in a poor, inadequate, or unfavorable manner; frequently used as a prefix in compound adjectives.

- The soldiers were ill-prepared for the cold winter weather.
- The company was ill-equipped to handle such a massive influx of customer complaints during the holiday season.

### 5. problems or harm

noun · CEFR C1 · Literary · Formal

problems, troubles, or things that cause suffering.

For teachers: problems, misfortunes, or social ailments; often used in the plural to describe broad issues.

- The politician promised to fix the many ills of modern society.
- The philosopher argued that greed was the root of all social ills, poisoning the relationships between different classes.

## Examples

- He stayed home from work because he felt ill.
- After eating the undercooked seafood, several guests began to feel ill and had to leave the party early.
- The sudden closure of the factory left many families in an ill position, struggling to meet their basic needs while searching for alternative employment in a stagnant market.

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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.