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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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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

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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 Science Words Every College Graduate Should Know

How do bats "see" in the dark? Why do ocean waves break parallel to the shore, no matter what direction they come from? What is the psychiatric disorder whereby people feign illness in order to gain medical attention? How do online stores keep credit card numbers secret from hackers?

The latest title in the best-selling 100 Words series, 100 Science Words Every College Graduate Should Know (Houghton Mifflin, April 5, 2006), provides simple answers to these and dozens of other questions about the fundamental concepts of science and technology.

Almost every day there are new facts and ideas discussed in the media about the makeup of the universe, the roles genes play in disease, the dangers of sweeping environmental change, and countless other things. People who are unfamiliar with the key words of science may not be able to fathom the rapid advances and developments taking place around them — even when they hit close to home.

Are you up to the challenge? Find out by reading 100 Science Words Every College Graduate Should Know, by the Editors of the American Heritage® Dictionaries. A wide variety of new and established terms are discussed, including absolute zero, anaphylaxis, cryptography, echolocation, game theory, Kuiper belt, mitochondrion, Munchausen syndrome, quantum mechanics, and refraction. Each term is defined in clear, nontechnical language, with examples showing the importance of the word both in its field and in daily life.

This book will appeal not only to college graduates, but to anyone with an interest in scientific concepts and the latest breakthroughs in the news.


The following is the entire list of 100 words:


absolute zero
agoraphobia
alga
algorithm
allele
alternating current
amygdala
anaphylaxis
angiogenesis
apoptosis
archaeon
artesian well
ATP
bandwidth
Beringia
big bang
black hole
Brownian motion
Cambrian Explosion
capacitor
carbon sequestration
centripetal force
chemosynthesis
cognitive dissonance
complementarity
cryptography
cyanobacterium
cyclone
dendrochronology
echolocation
endorphin
estivation
eutrophication
Fibonacci sequence
fission
fundamental force
game theory
genome
gluon
heliocentrism
histone
hominin
hypha
imaginary number
interferon
ischemia
isomer
junk DNA
krill
KT boundary
Kuiper belt
kwashiorkor
logic gate
magnetosphere
megabyte
melanoma
mitochondrion
monotreme
monsoon
Munchausen syndrome
nanotube
Neanderthal
nosocomial infection
obligate
orbital
pahoehoe
Pavlovian
phenotype
pheromone
photoelectric
photon
piezoelectric effect
placebo
prion
prophylaxis
protein folding
protolanguage
quantum mechanics
radiometric dating
rain shadow
refraction
REM sleep
retrovirus
roentgenium
sex
sociobiology
solar wind
superposition
telomere
teratogen
theory
tidal force
time dilation
Universal Time
urea
vestigial
wave function
xerophyte
yolk
zero


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