A root is a word that does not have a prefix in front of the word or a suffix at the end of the word. The root word is the primary lexical unit of a word, and of a word family, which carries the most significant aspects of semantic content and cannot be reduced into smaller constituents. Content words in nearly all languages contain, and may consist only of, root morphemes. However, sometimes the term "root" is also used to describe the word minus its inflectional endings, but with its lexical endings in place. For example, chatters has the inflectional root or lemmachatter, but the lexical root chat. Inflectional roots are often called stems, and a root in the stricter sense may be thought of as a monomorphemic stem. The traditional definition allows roots to be either free morphemes or bound morphemes. Root morphemes are essential for affixation and compounds. However, in polysynthetic languages with very high levels of inflectional morphology, the term "root" is generally synonymous with "free morpheme". Many such languages have a very restricted number of morphemes that can stand alone as a word: Yup'ik, for instance, has no more than two thousand.
Examples
The root of a word is a unit of meaning and, as such, it is an abstraction, though it can usually be represented alphabetically as a word. For example, it can be said that the root of the English verb formrunning is run, or the root of the Spanish superlative adjective amplísimo is ampli-, since those words are clearly derived from the root forms by simple suffixes that do not alter the roots in any way. In particular, English has very little inflection and a tendency to have words that are identical to their roots. But more complicated inflection, as well as other processes, can obscure the root; for example, the root of mice is mouse, and the root of interrupt is, arguably, rupt, which is not a word in English and only appears in derivational forms. The root rupt can be written as if it were a word, but it is not. This distinction between the word as a unit of speech and the root as a unit of meaning is even more important in the case of languages where roots have many different forms when used in actual words, as is the case in Semitic languages. In these, roots are formed by consonants alone, and speakers elaborate different words from the root by inserting different vowels. For example, in Hebrew, the root gdl represents the idea of largeness, and from it we have gadol and gdola, gadal "he grew", higdil "he magnified" and magdelet "magnifier", along with many other words such as godel "size" and migdal "tower". Roots and reconstructed roots can become the stock-in-trade of etymology.
Secondary roots
Secondary roots are roots with changes in them, producing a new word with a slightly different meaning. In English, a rough equivalent would be to see conductor as a secondary root formed from the root to conduct. In abjad languages, the most familiar of which are Arabic and Hebrew, in which families of secondary roots are fundamental to the language, secondary roots are created by changes in the roots' vowels, by adding or removing the long vowelsa, i, u, e and o. In addition, secondary roots can be created by prefixing, infixing, or suffixing. There is no rule in these languages on how many secondary roots can be derived from a single root; some roots have few, but other roots have many, not all of which are necessarily in current use. Consider the Arabic language:
مركز or meaning ‘centralized ’, from ‘centre’, from ‘plant into the earth, stick up ’. This in turn has derived words مركزي , meaning 'central', مركزية , meaning 'centralism' or 'centralization', and لامركزية, 'decentralization'
أرجح or meaning ‘oscillated ’, from ‘swing ’, from ‘weighed down, preponderated ’.
محور or meaning ‘centred, focused ’, from meaning ‘axis’, from ‘turned ’.
مسخر , تمسخر meaning ‘mocked, made fun ', from مسخرة meaning ‘mockery’, from سخر ‘mocked ’." Similar cases may be found in other Semitic languages such as Hebrew, Syriac, Aramaic, Maltese language and to a lesser extent Amharic.
Similar cases occur in Hebrew, for example Israeli Hebrew √mqm ‘locate’, which derives from Biblical Hebrewmåqom ‘place’, whose root is √qwm ‘stand’. A recent example introduced by the Academy of the Hebrew Language is midrúg ‘rating’, from midrág, whose root is √drg ‘grade’." According to Ghil'ad Zuckermann, "this process is morphologically similar to the production of frequentative verbs in Latin, for example:
iactito ‘to toss about’ derives from iacto ‘to boast of, keep bringing up, harass, disturb, throw, cast, fling away’, which in turn derives from iacio ‘to throw, cast’.
Consider also Rabbinic Hebrew √trm ‘donate, contribute’, which derives from Biblical Hebrew t'rūmå ‘contribution’, whose root is √rwm ‘raise’; cf. Rabbinic Hebrew √tr` ‘sound the trumpet, blow the horn’, from Biblical Hebrew t'rū`å ‘shout, cry, loud sound, trumpet-call’, in turn from √rw`." and it describes the suffix.
