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HOW TO USE THE DICTIONARY

Learn what the dictionary tells you about words.

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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.

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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

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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.

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AMERICAN HERITAGE DICTIONARY APP

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

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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.

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OPEN DICTIONARY PROJECT

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

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100 Words
100 Words Every High School Graduate Should Know

The editors of the American Heritage® dictionaries have compiled a list of 100 words they recommend every high school graduate should know.

"The words we suggest," says senior editor Steven Kleinedler, "are not meant to be exhaustive but are a benchmark against which graduates and their parents can measurethemselves. If you are able to use these words correctly, you are likely to have a superior command of the language."


The following is the entire list of 100 words:

abjure
abrogate
abstemious
acumen
antebellum
auspicious
belie
bellicose
bowdlerize
chicanery
chromosome
churlish
circumlocution
circumnavigate
deciduous
deleterious
diffident
enervate
enfranchise
epiphany
equinox
euro
evanescent
expurgate
facetious
fatuous
feckless
fiduciary
filibuster
gamete
gauche
gerrymander
hegemony
hemoglobin
homogeneous
hubris
hypotenuse
impeach
incognito
incontrovertible
inculcate
infrastructure
interpolate
irony
jejune
kinetic
kowtow
laissez faire
lexicon
loquacious
lugubrious
metamorphosis
mitosis
moiety
nanotechnology
nihilism
nomenclature
nonsectarian
notarize
obsequious
oligarchy
omnipotent
orthography
oxidize
parabola
paradigm
parameter
pecuniary
photosynthesis
plagiarize
plasma
polymer
precipitous
quasar
quotidian
recapitulate
reciprocal
reparation
respiration
sanguine
soliloquy
subjugate
suffragist
supercilious
tautology
taxonomy
tectonic
tempestuous
thermodynamics
totalitarian
unctuous
usurp
vacuous
vehement
vortex
winnow
wrought
xenophobe
yeoman
ziggurat


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