illness

Compared meaning: the state of being ill (noun).

比较义项：患病、生病的状态（名词）。

• illness 本词

  The more general, neutral word for being unwell; used for both short and long-term or serious conditions, and common in formal or medical contexts.

  更通用、更中性的“患病”说法，可指短期或长期、较严重的健康问题，常用于正式或医学语境。

  Her long illness kept her in and out of hospital for two years.

  她长期患病，两年里反复进出医院。

• sickness

  Common in everyday British English, especially in fixed phrases about work and pay, such as sickness leave or sick pay; can sound slightly less formal than illness.

  在英式英语的日常表达中很常见，尤其用于与工作、薪酬相关的固定搭配，如 sickness leave（病假）或 sick pay（病假工资），语气比 illness 略不那么正式。

  He didn't get paid because he'd used up all his sickness leave.

  他没拿到工资，因为他的病假已经用完了。

Illness and sickness are close in meaning and often interchangeable. Illness is more general and neutral, used for short or long-term health problems, common in medical writing. Sickness is common in British English, in phrases like sickness leave. Sickness meaning nausea is not compared.

这两个词在“生病”这一义项上非常接近，常可互换；但 sickness 在英式英语中更常与 pay/leave/benefit 等搭配，illness 更中性、更常泛指持续或严重的健康问题。这里不比较 sickness 的另一义项“恶心、晕动症”（如 travel sickness、morning sickness）。