Root Words

Glossary of Grammatical and Rhetorical Terms - Definition and Examples

root word - hope
The noun hope is a root word. Complex words that are derived from hope include hopeful, hopefully, hopefulness, hopeless, and hopelessness. (Malte Mueller/Getty Images)


In English grammar and morphology, a root is a word or word element (in other words, a morpheme) from which other words grow, usually through the addition of prefixes and suffixes. Also called a root word.

In Greek and Latin Roots (2008), T. Rasinski et al. define root as "a semantic unit. This simply means that a root is a word part that means something. It is a group of letters with meaning."

See Examples and Observations below. Also, see:


From the Old English, "root"
Examples and Observations

  • "Latin is the most common source of English root words; Greek and Old English are the two other major sources.

    "Some root words are whole words and others are word parts. Some root words have become free morphemes and can be used as separate words, but others cannot. For instance, cent comes from the Latin root word centum, meaning hundred. English treats the word as a root word that can be used independently and in combination with affixes, as in century, bicentennial and centipede. The words cosmopolitan, cosmic and microcosm come from the Greek root word kosmos, meaning universe; cosmos is also an independent root word in English." (Gail Tompkins, Rod Campbell, David Green, and Carol Smith, Literacy for the 21st Century: A Balanced Approach. Pearson Australia, 2015)

    Free Morphs and Bound Morphs

    • "Because a root tells us more about the meaning of a word than anything else, the first thing we ask about a complex word is often: What is its root? Often a complex word has more than one root, as in blackbird. . . .

      "In our native and nativized vocabulary, roots can usually appear as independent words, for which reason they are called free morphs. This makes it particularly easy to find the roots of words like black-bird, re-fresh, and book-ish-ness. In Latin and Greek, roots most often do not occur as separate words: they are bound morphs, meaning they can only appear when tied to other components. For example, the root of concurrent is curr 'run.' which is not an independent word in English or even in Latin."
      (Keith Denning, Brett Kessler, and William R. Leben. English Vocabulary Elements, 2nd ed. Oxford University Press, 2007)

      Roots and Lexical Categories

      • "Complex words typically consist of a root morpheme and one or more affixes. The root constitutes the core of the word and carries the major component of its meaning. Roots typically belong to a lexical category, such as noun, verb, adjective, or preposition. . . . Unlike roots, affixes do not belong to a lexical category and are always bound morphemes. For example, the affix -er is a bound morpheme that combines with a verb such as teach, giving a noun with the meaning 'one who teaches.'"
        (William O'Grady, et al., Contemporary Linguistics: An Introduction, 4th ed. Bedford/St. Martin's, 2001)

      Simple and Complex Words

      • "[M]orphologically simple words, which contain only a single root morpheme, may be compared to morphologically complex words which contain at least one free morpheme and any number of bound morphemes. Thus, a word like 'desire' may be defined as a root morpheme constituting a single word. 'Desirable,' by contrast, is complex, combining a root morpheme with the bound morpheme '-able.' More complex again is 'undesirability' which comprises one root and three bound morphemes: un+desire+able+ity. Notice also how, in complex words of this sort, the spelling of the root may be altered to conform to the bound morphemes around it. Thus, 'desire' becomes 'desir-' while 'beauty' will be transformed into 'beauti-' in the formation of 'beautiful' and of the increasingly complex 'beautician.'" (Paul Simpson, Language Through Literature: An Introduction. Routledge, 1997)



        Also Known As:

        base, stem