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bad

US //ˈbæd// UK //bˈæd// bad
  1. 1 not good / low quality (adj.)
    A1 Beginner

    not good in quality, or not what you wanted.

    of poor quality, inadequate, or failing to meet a required standard.

    Example

    The weather was really bad yesterday, so we stayed inside all day.

    Example

    The company's reputation suffered after a series of bad reviews highlighted the inconsistent quality of their customer service.

    Usage

    Commonly used as a predicative adjective after linking verbs.
    Pitfall
    I feel badly about the mistake.
    I feel bad about the mistake.

    Use 'bad' after linking verbs like 'feel', 'look', or 'seem' to describe your state of mind or health.

  2. 2 behaving poorly (adj.)
    A1 Beginner

    used to describe a person or animal that does not follow the rules.

    behaving in a disobedient, mischievous, or socially unacceptable manner.

    Example

    The teacher told the student that his behavior in class was bad.

    Example

    The puppy was being bad again, chewing on the expensive leather sofa while its owners were in the other room.

    Teacher's tip

    Often used by parents or teachers when speaking to children.
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  1. 3 harmful or unhealthy (adj.)
    A2 Elementary

    something that can hurt your health or cause problems.

    having a deleterious effect on health, well-being, or safety.

    Example

    Eating too much sugar is bad for your teeth.

    Example

    Prolonged exposure to blue light from screens late at night is considered bad for maintaining a healthy sleep cycle.

    Usage

    Often followed by the preposition 'for'.
  2. 4 spoiled or rotten (adj.)
    B1 Intermediate

    food that is no longer safe to eat.

    referring to food that has decayed or perished and is no longer fit for consumption.

    Example

    Don't drink that milk; it smells like it has gone bad.

    Example

    The entire shipment of produce went bad because the refrigeration system failed during the long journey across the border.

    Usage

    Commonly used with the verb 'go' (e.g., 'the milk went bad').
  3. 5 excellent or cool (adj.)
    C1 Advanced Slang

    very good, stylish, or impressive.

    denoting excellence, stylishness, or impressive toughness; a case of semantic inversion.

    Example

    That new car he bought is so bad.

    Example

    In the eighties, 'bad' became a popular slang term to describe something that was actually incredibly impressive or fashionable.

    Teacher's tip

    This is a classic example of 'reclaimed' or 'inverted' slang where a negative word is used positively.
  4. 6 a mistake (n.)
    B1 Intermediate Informal

    a way to say you made a mistake.

    an admission of a mistake or fault, typically used in the phrase 'my bad'.

    Example

    I forgot to bring your book back today—my bad.

    Example

    When the waiter realized he had brought the wrong order to the table, he simply shrugged and said, 'My bad.'

    Usage

    Almost exclusively used in the fixed expression 'my bad'.

    Teacher's tip

    Tell students this is a very casual way to apologize for small errors, but not for serious offenses.
  5. 7 unwanted goods (n.)
    C2 Proficiency Technical Economics

    something that people do not want and would pay to get rid of.

    an item or service that has negative utility to the consumer.

    Example

    Pollution is an example of an economic bad.

    Example

    Economists distinguish between 'goods' that increase utility and 'bads', such as household waste or industrial pollution, which individuals pay to avoid.

    Usage

    Used as a countable or uncountable noun in economic theory.

    Teacher's tip

    This is a highly specialized term; students will likely only see it in academic economic texts.
  6. 8 very much (adv.)
    B2 Upper Intermediate Informal American English

    very much or very strongly.

    used as an intensifier to mean 'to a great degree' or 'badly'.

    Example

    I want to go on vacation so bad.

    Example

    After working twelve hours straight without a break, he needed a glass of water really bad.

    Usage

    Usually follows verbs like 'want' or 'need'.

    Teacher's tip

    In formal writing, students should use 'badly' instead of 'bad' as an adverb.
Etymology 1

From Middle English bad, badde (“wicked, evil, depraved”), of uncertain origin. Perhaps a shortening of Old English bæddel (“hermaphrodite”) (for loss of -el compare Middle English muche from Old English myċel, and Middle English wenche from Old English wenċel), or at least related to it and/or to bǣ̆dan (“to defile”), compare Old High German pad (“hermaphrodite”). Alternatively, perhaps a loan from Old Norse into Middle English, compare Norwegian bad (“effort, trouble, fear”, neuter noun), East Danish bad (“damage, destruction, fight”, neuter noun), from the Proto-Germanic noun badą, whence also Proto-Germanic badōną (“to frighten”), Old Saxon undarbadōn (“to frighten”), Norwegian Nynorsk bada (“to weigh down, press”); ultimately from Proto-Indo-European *bʰedʰ- (“to bend, press, push, oppress”).

Etymology 2

From Middle English bad, from Old English bæd, first- and third-person singular indicative past tense of biddan (“to ask”).

Etymology 3

Unknown.

Idioms27 entries

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