noun
shell
shehl
noun
1
The hard outer covering of certain animals, such as snails, crabs, and turtles, or of eggs and nuts.
"The tortoise pulled its head into its shell at the first sign of danger."
"She cracked the shell of the walnut with a nutcracker."
2
An explosive projectile fired from artillery.
"The old bunker still bears scars from shells fired decades ago."
3
The outer frame or structure of something, especially when unfinished or empty inside.
"After the fire, only the blackened shell of the building remained."
4
A computer program that provides a command-line interface for interacting with an operating system.
"She wrote a small script to automate backups using the Bash shell."
verb
1
To remove the outer covering from something, such as a nut or pea.
"They spent the afternoon shelling peas from the garden."
2
To attack a target with artillery fire.
"The town was shelled repeatedly during the siege."
3
Informal: to pay out money, often reluctantly (usually "shell out").
"We had to shell out a fortune for the wedding venue."
How to Use Shell
Learner’s notesIn plain EnglishA hard protective covering (on an animal, egg, or nut); an explosive artillery round; an empty outer structure; or, in computing, the command-line program you type into.
Common mistake
In business, a "shell company" means an entity that legally exists but does no real business — don't confuse this figurative sense with the physical covering.
Common pairings
shell out
shell company
come out of your shell
egg shell
Word Forms
shelled past tense, shells plural, shells singular
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The tortoise pulled its head into its _____ at the first sign of danger.
Etymology
From Old English sċell, an ancient Germanic word meaning "shell" or "husk," related to modern "shale" and "scale."