# core

Pronunciation: US say "KOR" /kɔɹ/; UK say "KAW" /kɔː/

## Adjective

1. Forming the most important or essential part of something.
   - Simple: Being the most important part of something.
   - _Trust remains a core principle of the whole agreement._
   - _The committee focused on the core issues before anything else._

## Noun

2. The most important part of something or a group of things: its essence.
   - Simple: The most important part of an idea or thing.
   - _The core of her argument rested on a single statistic._
   - _At the core of the movement lay a demand for fairness._
3. An individual processor combined with others on a single integrated circuit to function together as one multi-core processor.
   - Simple: One of several processors built into a single computer chip.
   - _The operating system spread the workload across every available core._
   - _Developers optimized the program to use more than one core._
4. The central or innermost part of an object, area, or space, as distinct from its outer parts.
   - Simple: The middle or innermost part of a thing or place.
   - _Traffic clogs the core of the financial district every morning._
   - _The storm's most violent winds spun around its core._
8. The central part of a fruit, where the seeds or pips are held.
   - Simple: The middle part of a fruit that holds its seeds.
   - _After lunch, she tossed her apple core into the compost bin by the back door._
   - _After roasting, the pear's core was soft enough to eat._
5. The muscles of the trunk, chiefly those of the abdomen, lower back, and pelvis, that steady the spine and body during movement.
   - Simple: The set of muscles around your stomach and lower back.
   - _The trainer designed exercises to engage the core throughout the routine._
   - _Runners with a weak core often struggle to hold their posture._
6. A cylindrical sample of rock, ice, tissue, or other material, removed by drilling or with a hollow needle for examination.
   - Simple: A long round sample of rock, ice or body tissue taken out for testing.
   - _The team labeled each core before storing it for analysis._
   - _Ice cores from the glacier revealed centuries of climate data._
7. The central region of a reactor that houses the fuel and sustains the nuclear reaction.
   - Simple: The middle part of a nuclear reactor where the reaction happens.
   - _Operators monitored the core for sudden temperature spikes._
   - _A loss of coolant exposed part of the core to the air._
10. An online aesthetic or style built around a theme, usually named with the suffix -core, such as cottagecore or normcore.
   - Simple: A style or look popular online, built around one theme, with names like cottagecore.
   - _After cottagecore and normcore, it felt like every hobby had its own core on social media._
   - _Normcore was the core that captured the mid-2010s mood._
12. A piece of ferromagnetic material, such as soft iron, placed inside an electromagnet's windings to channel the magnetic field.
   - Simple: A piece of iron inside a coil that makes the magnet stronger.
   - _Engineers chose a laminated core to reduce energy loss._
   - _Removing the core sharply weakened the electromagnet._
13. A hollow cardboard cylinder around which a long web of paper or plastic is wound into a roll.
   - Simple: The hollow cardboard tube in the middle of a roll of paper or tape.
   - _The printer mounts each roll on a spindle that grips the cardboard core._
   - _A bent core can cause the whole roll of film to wind unevenly._

## Verb

9. To remove the seed-bearing center from an apple or similar fruit.
   - Simple: To take out the middle part of a fruit where the seeds are.
   - _He likes to core the apples before slicing them into rings._
   - _The chef cored a dozen pears for the tart._
11. To drill or cut through the central part of something, especially to remove a cylindrical piece or sample.
   - Simple: To drill a round hole through something, often to take out a sample.
   - _The crew will core the concrete slab to install the cable._
   - _The plumbers cored the concrete wall to run a new water pipe through it._

## Other meanings

- (noun) An atom's nucleus together with its inner electrons, leaving out the outer valence electrons.
- (noun) The inner material held between the surface layers of a structured composite sandwich panel.
- (noun) The central fissile mass at the heart of a fission weapon.
- (adjective) Deeply and authentically immersed in the culture surrounding a board sport.
- (noun) Short for core memory: an old type of computer memory that used tiny magnetic rings, or a computer's main memory.
- (noun) In classification, the parts of a category most readily, or most probably, taken as belonging to it.
- (noun) The central interior of a folded protein, made up mostly of hydrophobic, water-avoiding amino acids.
- (noun) The portion of a mold that forms a cavity, recess, or hole within a cast or molded part.
- (noun) The bony projection forming the central axis of the horns in many animals.
- (noun) The principal and most diverse single-ancestor group within a broader clade or taxonomic group.
- (noun) The set of feasible allocations that no coalition of agents could improve upon by acting on its own.
- (noun) A refundable deposit charged when buying a rebuilt part, repaid once the old rebuildable part is returned; also the returned part itself.
- (noun) A miner's spell of underground working time; a shift.
- (noun) A sheep disease in which parasitic worms infest the liver.
- (noun) A group of people gathered together, a company or band.
- (noun) An ancient Hebrew and Phoenician measure of capacity for grain and liquids, also spelled cor.

## Origin

**Meanings 1–9, 11–13** — Middle English had core, kore, coor ("apple-core, pith"), but where it came from is obscure and uncertain. It may be a native English word related to Old English corn ("seed, grain"). Other possible sources are Old French cuer ("heart"), from Latin cor, and Old French cors ("body"), from Latin corpus.
**Meaning 10** — From -core, ultimately derived from Etymology 1.

Source: DictionaryAI, https://dictionaryai.com/define/core (written from Wiktionary data, CC BY-SA 4.0: https://creativecommons.org/licenses/by-sa/4.0/).