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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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Guide to the Indo-European Roots Appendix

This dictionary carries the etymology of the English language to its logical and natural conclusion, for if the documentary history of words is of interest and value, so is their reconstructed prehistory. The historical component is given in the etymologies, after the definitions in the main body of the dictionary. This appendix supplies the prehistoric component, tracing the ultimate Indo-European derivations of those English words that are descended from a selected group of Indo-European roots.

In the appendix, the form given in boldface type at the head of each entry is, unless otherwise identified, an Indo-European root in its basic form. The basic root form is followed in some cases by one or more variants, also in boldface type. Then the basic reconstructed meaning or meanings of the root are given. Meanings that are different parts of speech are separated by a semicolon:

kei-1 To lie; bed, couch; beloved, dear.
pelə-2 Flat; to spread.
leg- To collect; with derivatives meaning “to speak.”

After the basic meaning there may appear further information about the phonological shape or nature of the root:

skei- To cut, split. Extension of sek-.
kwr̥mi- Worm. Rhyme word to *wr̥mi‑, worm (see wer-2).
pā- To protect, feed. Oldest form *peh2‑, colored to *pah2‑, becoming *pā-.
[līk- Body, form; like, same. Germanic root.

Most, but not all, of the additional information is self-explanatory. In the first two examples, the boldface forms sek- and wer-2 are cross-references to those roots, which are main entries in this appendix. Every boldface form appearing in the text of an entry is such a cross-reference. In the example pā- the forms *peh2‑, *pah2‑, and *pā- represent older root forms; the nature of these changes is explained in the essay with “Speech Sounds and Their Alternations” (see the print dictionary). The entries līk- and re- are not, strictly speaking, Indo-European, since they are represented in only one branch of the family, but they are included, within boldface brackets, because of the number of English words among their descendants.

The text of each entry describes in detail the development of Modern English words from the root. Each numbered section of an entry begins with a list, in small capitals, of the Modern English words derived from a particular form of the root. (This list may be preceded by an intermediate step; see further below.) The simple (uncompounded) derivatives are given first; the compounds follow, separated from them by a semicolon. In some cases no further semantic or morphological development needs to be explained, and the lemma, the historically attested representative of the root, is given next, as avis at the entry awi-:

awi- Bird. I. 1.avian, aviary, aviation; aviculture, avifauna, bustard, ocarina, osprey, ostrich, from Latin avis, bird.

Much more commonly, however, intermediate developments require explanation. These intermediate stages are reconstructions representing a word stem in Indo-European that is necessary to explain the lemma following it (see the section “Grammatical Forms and Syntax” in the print dictionary). The reconstructed forms are not historically attested; they are preceded by an asterisk (*) to note this fact. Sometimes earlier or later developments of the intermediate forms are given in parentheses, as in the example of stā- below. In these cases the symbol < is used to mean “derived from” and the symbol > is used to mean “developed into.” Intermediate stages that are in fact attested (such as the stages between Latin avis and English bustard in the example above) are usually not given in the appendix, but in the etymology of the word in the main vocabulary of the dictionary. The following terms are used to describe typical morphological processes of Indo-European:

Full-grade form:

 A form with e-vocalism (the basic form); so identified for descriptive contrast.

O-grade form:

 A form with o-vocalism:

dhers- O-grade form *dhors-

Zero-grade form:

 A form with zero-vocalism:

men-1I. Zero-grade form *mn̥-.

Lengthened-grade form:

 A form with lengthened vocalism:

ked-1. Lengthened-grade form *kēd-.

Secondary full-grade form:

 A new full-grade form created by inserting the fundamental vowel e in the zero-grade form of an extended root:

stā-V. Zero-grade extended root *stū- (< *stuə‑).... VI. Secondary full-grade form *steuə-.

Basic form:

 The unchanged root; so identified for descriptive contrast.

Suffixed form:

 A form with one or more suffixes, written with an internal hyphen:

laks- Suffixed form *laks-o-.
maghu- Suffixed form *magho-ti-.
mel-21. Suffixed (comparative) form *mel-yos-.

Prefixed form:

 A form with a prefix, written with an internal hyphen:

op-6. … from prefixed form *co-op-

Extended form:

 A form with an extension or enlargement, written without internal hyphens:

pel-5II. Extended form *pelh2-.

Nasalized form:

 A form with a nasal infix, written with internal hyphens:

tag-1. Nasalized form *ta-n-g-.

Reduplicated form:

 A form prefixed by its own initial consonant followed by a vowel:

segh-6. Reduplicated form *si-sgh-.

Expressive form:

 A form with “expressive gemination” (doubling of the final consonant), written without internal hyphens:

gal-3. Expressive form *gall-.

Compound form:

 A form compounded with a form of another root, written with internal hyphens:

dem-3. Compound form *dems-pot-

Shortened form:

 A form with shortened vocalism:

syū-III. Suffixed shortened form *syu-men-.

Reduced form:

 A form with loss of one or more sounds:

ambhi1. Reduced form *bhi.

Oldest root form:

 A root form showing a laryngeal (h1, h2, h3, hx, etc. ) in a position, typically at the beginning or end of a root, where it is preserved in only a few Indo-European languages, such as Greek or Hittite:

ster-3 Star. Oldest form *h2ster-.

Variant form:

 A form altered in any way other than those described in the above categories:

deru-2. Variant form *dreu-.

These terms can be combined freely to describe in as much detail as necessary the development from the root to the lemma.

dhē(i)-1. Suffixed reduced form *dhē-mnā-. female, feme, feminine; effeminate, from Latin fēmina, woman (< “she who suckles”).
gerə-11. Suffixed lengthened-grade form *gērə-s-. ageratum, geriatrics, from Greek gēras, old age.
petə-2. Suffixed (stative) variant zero-grade form *pat-ē-. patent, patulous, from Latin patēre, to be open.

In order to emphasize the fact that English belongs to the Germanic branch of Indo-European and give precedence to directly inherited words in contrast to words borrowed from other branches, the intermediate stages in Germanic etymologies are covered in fuller detail. The Common or Proto-Germanic (here called simply Germanic) forms underlying English words are always given. Where no other considerations intervene, Germanic is given first of the Indo-European groups, and Old English is given first within Germanic, although this order of precedence is not rigidly applied.

The final item in most entries is an abbreviated reference, in brackets, to Julius Pokorny’s Indogermanisches Etymologisches Wörterbuch [Indo-European Etymological Dictionary] (Bern, 1959). This, the standard work of reference and synthesis in the Indo-European field, carries a full range of the actual comparative material on which the roots are reconstructed. Our appendix presents only those aspects of the material that are directly relevant to English. For example, the English word many is found at the root menegh‑, “copious.” This entry describes the transition of the Indo-European form through Germanic *managa- to Old English manig, mænig, “many.” It does not cite the comparative evidence from outside English and Germanic on which this assertion is based, but it refers to “Pokorny men(e)gh- 730.” The entry men(e)gh- on page 730 in Pokorny’s dictionary cites, in addition to the Old English word, the forms attested in Sanskrit, Celtic, Gothic, Old High German, Old Norse, Slavic, and Lithuanian, from which the reconstruction of the root was made. These references should serve as a reminder that the information given in this appendix is assertive rather than expository and that the evidence and evaluation upon which its assertions are based are not presented here.


* unattested
< derived from
> developed into

Parentheses within a form enclose sound(s) or letter(s) sometimes or optionally present.

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