# core

/ˈkɔɹ/ (US) · /kˈɔː/ (UK)

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

## Senses

### 1. center of fruit

noun · CEFR B1

the hard central part of a fruit, such as an apple or pear, that contains the seeds.

For teachers: the central portion of certain fleshy fruits, such as apples or pears, containing the seeds and typically having a tough or fibrous texture.

- She ate the whole apple except for the core.
- After peeling the fruit, the chef used a specialized tool to remove the core without bruising the surrounding flesh.

### 2. most important part

noun · CEFR B2

the most important or central part of a system, organization, or idea.

For teachers: the foundational or most essential part of an aggregate, system, or abstract concept; the essence.

- The core of the problem is that we don't have enough money.
- At the core of his philosophical argument lies the belief that individual liberty must always outweigh collective security.

### 3. center of a planet or star

noun · CEFR B2

the central part of a planet or star, which is often very hot or solid.

For teachers: the innermost layer of a celestial body, such as the Earth's molten outer core and solid inner core.

- Scientists study the Earth's core to understand the planet's magnetic field.
- The fusion reactions occurring within the star's core generate the immense pressure required to prevent gravitational collapse.

### 4. computing processor

noun · CEFR C1 · Technical

one of the independent processing units in a computer's CPU.

For teachers: an independent processing unit within a central processing unit (CPU) that can execute program instructions.

- This new laptop has a processor with eight cores for faster performance.
- The software is optimized for multi-core architectures, allowing it to distribute heavy workloads across several processing units simultaneously.

### 6. essential

adjective · CEFR B2 · Academic

describing the most important or basic parts of something.

For teachers: constituting the essential, foundational, or most significant part of a whole.

- Math and English are core subjects that every student must take.
- The company decided to sell its secondary businesses to focus on its core competencies and long-term stability.

Usage: Usually placed before the noun.

### 7. to remove the center

verb · CEFR C1 · Technical

to take the center part out of a fruit.

For teachers: to remove the central part or seeds from a fruit; to extract a cylindrical sample from a larger mass.

- You should peel and core the pears before boiling them in the syrup.
- The geologists spent the afternoon coring the glacier to obtain ice samples for climate analysis.

Usage: Transitive verb requiring a direct object.

## Examples

- The core of the apple contains the seeds.
- The government's new policy has environmental protection at its core, influencing every decision they make.
- Engineers must ensure the reactor core remains stable under extreme pressure to prevent a catastrophic failure of the entire power plant system.

---

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.