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!

bit 1 (bĭt)
Share:
n.
1. A small portion, degree, or amount: a bit of lint; a bit of luck.
2. A brief amount of time; a moment: Wait a bit.
3.
a. A short scene or episode in a theatrical performance.
b. A bit part.
4. An entertainment routine given regularly by a performer; an act.
5. Informal
a. A particular kind of action, situation, or behavior: got tired of the macho bit.
b. A matter being considered: What's this bit about inflation?
6. Informal An amount equal to one eighth of a dollar: two bits.
7. Chiefly British A small coin: a threepenny bit.
Idioms:
a bit
To a small degree; somewhat: a bit warm.
bit by bit
Little by little; gradually.
do (one's) bit
To do one's part or contribute one's share.

[Middle English bite, morsel, from Old English bita; see bheid- in the Appendix of Indo-European roots.]

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2017 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
 
bit 2 (bĭt)
Share:
n.
1. The sharp part of a tool, such as the cutting edge of a knife or axe.
2. A pointed and threaded tool for drilling and boring that is secured in a brace, bitstock, or drill press.
3. The part of a key that enters the lock and engages the bolt and tumblers.
4. The tip of the mouthpiece on a pipe or a cigarette or cigar holder.
5. The metal mouthpiece of a bridle, serving to control, curb, and direct an animal.
6. Something that controls, guides, or curbs.
tr.v. bit·ted, bit·ting, bits
1. To place a bit in the mouth of (a horse, for example).
2. To check or control with or as if with a bit.
3. To make or grind a bit on (a key).
Idiom:
have/take the bit in one's teeth
To be uncontrollable; cast off restraint.

[Middle English bite, from Old English, act of biting; see bheid- in the Appendix of Indo-European roots.]

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2017 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
 
bit 3 (bĭt)
Share:
n.
Computers
A binary digit, having either the value 0 or 1, used to store or represent data.


The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2017 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
 
bit 4 (bĭt)
Share:
v.
Past tense and a past participle of bite.

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.