# sex

/ˈsɛks/ (US) · /sˈɛks/ (UK)

Source: https://englishreference.com/word/sex
Updated: 2026-06-19

## Senses

### 2. sexual activity

noun · CEFR B1

physical activity between people that is related to sexual pleasure.

For teachers: sexual activity, specifically sexual intercourse or other intimate physical acts.

- The book discusses how to have a healthy conversation about sex with your partner.
- The study examines the correlation between physical exercise and a healthy interest in sex among middle-aged adults.

Usage: uncountable in this sense.

### 3. people of one category

noun · CEFR B2

all the people of one biological group, such as all women or all men.

For teachers: the members of a particular biological sex considered collectively.

- The club was open to members of either sex.
- The legislation was designed to prevent discrimination against either sex in the workplace.

### 4. to identify biological sex

verb · CEFR C1 · Technical

to find out if an animal is male or female.

For teachers: to determine the biological sex of an organism, typically an animal or a plant.

- It can be quite difficult to sex some species of birds just by looking at them.
- The researchers had to sex the hatchlings immediately to ensure an accurate count of the male-to-female ratio in the population.

Usage: transitive verb.

## Examples

- The doctor asked for the sex of the baby.
- Researchers found that the sex of the animal influenced how it responded to the new environment.
- While the study initially focused on biological sex, the researchers eventually expanded their scope to include a wider range of social and environmental factors.

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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.