use-icon

HOW TO USE THE DICTIONARY

Learn what the dictionary tells you about words.

Get Started Now!

Some compound words (like bus rapid transit, dog whistle, or identity theft) don’t appear on the drop-down list when you enter them into the search window. If a compound term doesn’t appear in the drop-down list, try entering the term into the search window and then hit the search button (instead of the “enter” key). Alternatively, begin searches for compound terms with a quotation mark.

use-icon

THE USAGE PANEL

The Usage Panel is a group of nearly 200 prominent scholars, creative writers, journalists, diplomats, and others in occupations requiring mastery of language. The Panelists are surveyed annually to gauge the acceptability of particular usages and grammatical constructions.

The Panelists

puzzle-icon

NEED HELP SOLVING A CROSSWORD PUZZLE?

Go to our Crossword Puzzle Solver and type in the letters that you know, and the Solver will produce a list of possible solutions.

open-icon

INTERESTED IN DICTIONARIES?

Check out the Dictionary Society of North America at http://www.dictionarysociety.com

open-icon

AMERICAN HERITAGE DICTIONARY APP

The new American Heritage Dictionary app is now available for iOS and Android.

scroll-icon

INDO-EUROPEAN & SEMITIC ROOTS APPENDICES

Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:

Indo-European Roots

Semitic Roots

The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.

open-icon

OPEN DICTIONARY PROJECT

Share your ideas for new words and new meanings of old words!

Start Sharing Now!

100-words-icon

See word lists from the best-selling 100 Words Series!

Find out more!

shell (shĕl)
Share:
n.
1.
a. The usually hard outer covering that encases certain organisms, such as insects, turtles, and most mollusks.
b. A similar outer covering on a nut or seed.
c. A similar outer covering on certain eggs, such as those of birds and reptiles; an eggshell.
d. The material that constitutes such a covering.
2. Something resembling or having the form of a shell, especially:
a. An external, usually hard, protective or enclosing case or cover.
b. A framework or exterior, as of a building.
c. A thin layer of pastry.
d. The external part of the ear.
3. Nautical
a. The hull of a ship.
b. A light, long, narrow racing boat propelled by rowers.
4. A small glass for beer.
5.
a. An artillery projectile containing an explosive charge.
b. A metal or cardboard case containing the charge and primer for a piece of firearms ammunition, especially one also containing shot and fired from a shotgun.
6. An attitude or a manner adopted to mask one's true feelings or to protect one from perceived or real danger: Embarrassed, she withdrew into a shell.
7. Physics
a. A set of electron orbitals having nearly the same energy and sharing the same first quantum number.
b. Any of the stable states of other particles or collections of particles (such as the nucleons in an atomic nucleus) at a given energy or small range of energies.
8.
a. A usually sleeveless and collarless, typically knit blouse.
b. A thin, usually waterproof or windproof outer garment for the upper body.
9. Computers A program that works with the operating system as a command processor, used to enter commands and initiate their execution.
10. A company or corporation created by a second company or corporation for the purposes of facilitating a particular transaction, especially one that is intended to be concealed.
v. shelled, shell·ing, shells
v.tr.
1.
a. To remove the shell of; shuck: shell oysters.
b. To remove from a shell: shell peas.
2. To separate the kernels of (corn) from the cob.
3. To fire shells at; bombard.
4.
a. To defeat decisively.
b. Baseball To hit the pitches of (a pitcher) hard and with regularity: shelled the pitcher for eight runs in the first inning.
v.intr.
1. To shed or become free of a shell.
2. To look for or collect shells, as on a seashore: spent the day shelling on Cape Cod.
Phrasal Verb:
shell out Informal
To hand over; pay: had to shell out $500 in car repairs.

[Middle English, from Old English scell; see skel-1 in the Appendix of Indo-European roots.]

shell adj.
sheller n.

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2017 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
 

This website is best viewed in Chrome, Firefox, Microsoft Edge, or Safari. Some characters in pronunciations and etymologies cannot be displayed properly in Internet Explorer.