English Reference

Word

shell

US/ˈʃɛɫ/

UK/ʃˈɛl/

Definitions

01animal/egg/nut covering

A2 · Elementary Countable noun

n. the hard outer part that protects some animals, eggs, or nuts.

n. the hard, protective external covering of a mollusc, crustacean, bird's egg, or nut.

“The children collected beautiful white shells on the beach.”

“The turtle retreated into its shell as soon as it sensed the vibration of approaching footsteps.”

Synonyms

02explosive weapon

B2 · Upper Intermediate Countable noun

n. a metal container filled with explosives that is fired from a large gun.

n. a hollow projectile containing an explosive charge, typically fired by artillery or mortars.

“The soldiers loaded the heavy shells into the cannon.”

“The coastal battery was equipped to fire high-explosive shells capable of reaching targets several miles out at sea.”

03empty structure

B2 · Upper Intermediate Countable noun

n. the basic outer frame of a building or object without the inside parts.

n. the external framework or walls of a structure, especially one that is unfinished or has been gutted.

“After the fire, only the brick shell of the house remained.”

“The developers purchased the industrial shell and planned to convert the interior into modern luxury lofts.”

04computing interface

C1 · Advanced Countable noun Computing Technical

n. a program that lets a user talk to a computer by typing commands.

n. a software interface that provides access to an operating system's services, often via a command-line interpreter.

“You can type the command directly into the shell to move the file.”

“Experienced administrators often prefer working in a Unix shell because it allows for complex automation through scripting.”

Synonyms

terminalcommand line

Antonyms

05to remove a covering

B1 · Intermediate Cooking

v. to take the hard outer part off something, like peas or nuts.

v. to remove the pod, husk, or shell from a seed or fruit.

“We sat on the porch and shelled peas for dinner.”

“The recipe requires you to shell the pistachios before grinding them into a fine paste for the cake.”

Synonyms

shuckpeelhull

06to attack with explosives

B2 · Upper Intermediate

v. to fire large guns or explosives at a place.

v. to bombard a location with artillery shells.

“The navy began to shell the enemy's fort from the sea.”

“The city was shelled for three consecutive days, forcing the civilian population to seek refuge in underground bunkers.”

Synonyms

07to pay money

B2 · Upper Intermediate Informal

phr.v. to pay for something, especially when it is expensive or you do not want to.

phr.v. to disburse a significant amount of money, typically with a sense of reluctance or obligation.

“I had to shell out a lot of money to fix my car.”

“Homeowners often have to shell out thousands of dollars for unexpected repairs when purchasing an older property.”

Usage

Always used as 'shell out'.

Synonyms

payspendfork out

Collocations

Common phrases and expressions where native English speakers use the word “shell” in context.

01. shell companies

Etymology

From Proto-Indo-European (s)kelH- ("to split, cleave"), the root threaded through Germanic sound laws to yield Proto-Germanic skaljō, Proto-West Germanic *skallju, Old English sċiell, and Middle English schelle. The cognates are scattered: West Frisian skyl ("peel, rind"), Dutch schil ("peel, skin, rind"), Low German Schell ("shell, scale"), Irish scelec ("pebble"), and Old Church Slavonic сколика (skolika, "shell"). The sense of something split off or separated — a hard outer covering that cleaves from what it encloses — has remained stable across two millennia.

A doublet, sheal, survives in dialectal use.

The computing sense, emerging in the mid-twentieth century, borrows the metaphor of an outer boundary: the shell as interface, mediating between user and operating-system internals.

Etymology adapted from Wiktionary, available under CC BY-SA 4.0.

Word family

NOUN

shell(A2)

Idioms

This entry

Exam level
CambridgeCambridgeCambridge English QualificationsThe exam suite from Cambridge University Press & Assessment, from A1 Movers up to C2 Proficiency. The benchmark names double as CEFR labels.A2 KeyIELTSIELTSInternational English Language Testing SystemThe 0–9 band test co-owned by the British Council, IDP, and Cambridge. Used for university entry, work, and migration.3.0–4.0TOEFL iBTTOEFL iBTTest of English as a Foreign Language, Internet-Based TestETS's academic English test, the standard route for US university admissions. Scored 0–120, with a 1–6 scale since 2026.1–6 scale: 2.0–2.524–43TOEICTOEICTest of English for International CommunicationETS's workplace English test, big in Japan and Korea. Listening & Reading scores 10–990 and tops out at C1.225–549
Frequency
Common
Level
A2 · Elementary
Updated

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