core

Meanings

1. 1nounusually singular

   The most important central part of something, on which the rest depends.

   Grammar: Usually singular with the: the core of the problem.

   Patterns

   • the core of something
   • at the core of something

   Honesty is at the core of our family's values.

   The core of the argument is simple: people need clean water.

   A small core of volunteers keeps the club running.

2. 2nouncountable

   The hard center of a fruit such as an apple, which holds the seeds.

   Grammar: Often what you throw away: an apple core.

   Patterns

   • the core of an apple

   He ate the whole apple, right down to the core.

   Cut out the core before you slice the pear.

3. 3nouncountabletechnical

   The innermost layer of a planet or the center of a nuclear reactor.

   Grammar: A technical sense: Earth's core.

   Patterns

   • the core of a planet

   Earth's core is made mostly of iron and nickel.

   Engineers cooled the reactor core after the fault.

4. 4adjectivebefore a noun

   Most basic and important, forming the central part of something.

   Grammar: Always before a noun: core skills, not skills that are core.

   Patterns

   • a core subject

   Math and reading are core subjects in most schools.

   The company dropped products outside its core business.

5. 5verbtransitive

   To remove the hard central part from a fruit.

   Grammar: Takes an object: core the apples.

   Patterns

   • core something

   Core the apples and slice them thinly.

   She cored three pears for the tart.

Word forms

Common combinations

core values

Respect is one of our core values.

core business

The firm sold off units outside its core business.

to the core

The scandal shook the party to the core.

core curriculum

Science is part of the core curriculum.

rotten to the core

The investigation showed the system was rotten to the core.

Synonyms and how they differ

heart

Heart often carries emotional or lively overtones, as in the heart of the city, while core is more neutral and structural.

center

Center is simply the middle point, while core suggests the most essential part, not only the middle.

essence

Essence refers to the basic nature of something, usually an idea, rather than a physical inside.

kernel

Kernel is a small essential part, often of an idea or a nut, and sounds more literary.

Opposites

Word family

corer noun

a kitchen tool for removing fruit cores

hard-core adjective

extremely committed or intense

multicore adjective

having several processing cores in a computer chip

Commonly confused: core or corps? core or corpse?

Practice

Make it your own

Write a sentence using “core”, then check it and compare it with the examples above.

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