In linguistics, reduplication is a morphological process in which the root or stem of a word, part of that, or the whole word is repeated exactly or with a slight change.
The classic observation on the semantics of reduplication is Edward Sapir's: "Generally employed, with self-evident symbolism, to indicate such concepts as distribution, plurality, repetition, customary activity, increase of size, added intensity, continuance."p. 76. Sapir, Edward. 1921. Language: An Introduction to the Study of Speech. New York: Harcourt, Brace and Company. It is used in inflections to convey a grammatical function, such as plurality or intensification, and in lexical derivation to create new words. It is often used when a speaker adopts a tone more expressive or figurative than ordinary speech and is also often, but not exclusively, iconic in meaning. It is found in a wide range of languages and language groups, though its level of linguistic productivity varies. Examples can be found in language as old as Sumerian, where it was used in forming some color terms, e.g. "white", "black".p. 31, Michalowski, Piotr. 2004. "Sumerian" in The Cambridge Encyclopedia of the World’s Ancient Languages, edited by Roger D. Woodard, 19-59. Cambridge University Press.
The most recent major contribution and reference on reduplication is by Dariush Borbor's Dictionary of Reduplication which gives a comprehensive, classified listing of reduplicates in Arabic, Armenian, Kurdish, Persian and Turkish, the major languages of the Middle East and Iran."Book Review, Dariush Borbor, Analytical Comparative Etymological Dictionary of Reduplication in the Major Languages of the Middle East and Iran" in The Iran and the Caucasus 30 (2026), by Saloumeh Gholami, 93-100. Brill.
Reduplication is the standard term for this phenomenon in the linguistics literature. Other occasional terms include cloning, doubling, duplication, repetition, and tautonymy (when it is used in biological taxonomies, such as Bison bison).
Typological description
Form Reduplication is often described phonologically in one of two ways: either (1) as reduplicated segments (sequences of consonants/vowels) or (2) as reduplicated prosodic units (syllables or moras). In addition to phonological description, reduplication often needs to be described morphologically as a reduplication of linguistic constituents (i.e. words, stems, roots). As a result, reduplication is interesting theoretically as it involves the interface between phonology and morphology.
The base is the word (or part of the word) that is to be copied. The reduplicated element is called the reduplicant, often abbreviated as RED or sometimes just R.
In reduplication, the reduplicant is most often repeated only once. In some languages, it can occur more than once, resulting in a tripled form, and not a duple as in most reduplication. Triplication is the term for this phenomenon of copying two times. Pingelapese has both forms. In this article, English translations of words are shown in apostrophes:
Basic verb Reduplication Triplication 'to sing' 'singing' 'still singing' 'to sleep' 'sleeping' 'still sleeping'
Triplication occurs in other languages, e.g. Ewe, Shipibo, Twi, Mokilese, Min Nan (Hokkien), Stau.
Sometimes gemination (i.e. the doubling of consonants or vowels) is considered to be a form of reduplication. The term dupleme has been used (after morpheme) to refer to different types of reduplication that have the same meaning.
Full and partial Full reduplication involves a reduplication of the entire word. For example, Kham derives reciprocal forms from reflexive forms by total reduplication:
'ourselves' → 'we (to) us' 'themselves' → 'they (to) them' (Watters 2002)
Another example is from Musqueam Halkomelem "dispositional" aspect formation:
'to capsize' → 'likely to capsize' 'to speak' → 'talkative' (Shaw 2004)
Partial reduplication involves a reduplication of only part of the word. For example, Marshallese forms words meaning 'to wear X' by reduplicating the last consonant-vowel-consonant (CVC) sequence of a base, i.e. base+CVC:
kagir 'belt' → kagirgir 'to wear a belt' (kagir-gir) takin 'sock' → takinkin 'to wear socks' (takin-kin) (Moravsik 1978)
Many languages often use both full and partial reduplication, as in the Motu example below:
Base verb Full reduplication Partial reduplication mahuta 'to sleep' mahutamahuta 'to sleep constantly' mamahuta 'to sleep (plural)' (mahuta-mahuta) (ma-mahuta)
Reduplicant position Reduplication may be initial (i.e. prefixal), final (i.e. suffixal), or internal (i.e. infixal), e.g.
Initial reduplication in Agta (CV- prefix): 'afternoon' → 'late afternoon' 'a long time' → 'a long time (in years)' (ŋa-ŋaŋaj) (Healey 1960)
Final reduplication in Dakota (-CCV suffix): 'tall (singular)' → 'tall (plural)' (hãska-ska) 'good (singular)' → 'good (plural)' (Shaw 1980, Marantz 1982, Albright 2002)
Internal reduplication in Samoan (-CV- infix): savali 'he/she walks' (singular) → savavali 'they walk' (plural) (sa-va-vali) alofa 'he/she loves' (singular) → alolofa 'they love' (plural) (a-lo-lofa) (Moravcsik 1978, Broselow and McCarthy 1984) le tamaloa 'the man' (singular) → tamaloloa 'men' (plural) (tama-lo-loa)
Internal reduplication is much less common than the initial and final types.
Copying direction A reduplicant can copy from either the left edge of a word (left-to-right copying) or from the right edge (right-to-left copying). There is a tendency for prefixing reduplicants to copy left-to-right and for suffixing reduplicants to copy right-to-left:
Initial L → R copying in Oykangand Kunjen (a Pama–Nyungan language of Australia): → 'rain' (ed-eder) → 'straight' (alg-algal)
Final R → L copying in Sirionó: achisia → achisiasia 'I cut' (achisia-sia) ñimbuchao → ñimbuchaochao 'to come apart' (ñimbuchao-chao) (McCarthy and Prince 1996)
Copying from the other direction is possible although less common:
Initial R → L copying in Tillamook: 'eye' → 'eyes' 'break' → 'they break' (Reichard 1959)
Final L → R copying in Chukchi: nute- 'ground' → nutenut 'ground (abs. sg.)' (nute-nut) 'gopher' → 'gopher (abs. sg.)' (Marantz 1982)
Internal reduplication can also involve copying the beginning or end of the base. In Quileute, the first consonant of the base is copied and inserted after the first vowel of the base.
Internal L → R copying in Quileute: 'he put it on' → 'he put it on (frequentative)' (tsi-ts-ko) 'snow' → 'snow here and there' (tu-t-ko:jo’) (Broselow and McCarthy 1984)
In Temiar, the last consonant of the root is copied and inserted before the medial consonant of the root.
Internal R → L copying in Temiar (an Austroasiatic language of Malaysia): 'to shoot (perfective)' → 'to shoot (continuative)' 'to marry (perfective)' → 'to marry (continuative)' (Broselow and McCarthy 1984, Walther 2000)
A rare type of reduplication is found in Semai (an Austroasiatic language of Malaysia). "Expressive minor reduplication" is formed with an initial reduplicant that copies the first and last segment of the base:
→ 'to vomit' → 'appearance of nodding constantly' → 'monsoon rain' Diffloth 1973
With other morphological processes
All the examples above consist of only reduplication, which also often occurs with other phonological and morphological processes, such as vowel alternation, deletion and affixation of non-reduplicating material.
For instance, in Tz'utujil a new '-ish' adjective form is derived from other words by suffixing the reduplicated first consonant of the base followed by the segment . This can be written succinctly as . Below are some examples:
'red' → 'reddish' 'yellow' → 'yellowish' 'water' → 'watery' (Dayley 1985)
Somali has a similar suffix that is used in forming the plural of some nouns: -aC (where C is the last consonant of the base):
'ditch' → 'ditches' 'lump of meat' → 'lumps of meat' 'boy' → 'boys' (Abraham 1964)
This combination of reduplication and affixation is commonly referred to as fixed-segment reduplication.
In Tohono O'odham initial reduplication also involves gemination of the first consonant in the distributive plural and in repetitive verbs:
'ox' → 'ox (distributive)' (no-n-nowiu) 'rock' → 'rock (distributive)' (ho-h-hodai) 'dig out of ground (unitative)' → 'dig out of ground (repetitive)' (ko-k-kow) 'hit (unitative)' → 'hit (repetitive)' (Haugen forthcoming)
Sometimes gemination can be analyzed as a type of reduplication.
Phonological processes, environment, and reduplicant-base relations
overapplication underapplication backcopying – A putative phenomenon of over-application in the reduplicant of a process triggered by the reduplicant in the base base-reduplicant "identity" (OT terminology: BR-faithfulness) tonal transfer/non-transfer
Function and meaning In the Malayo-Polynesian family, reduplication is used to form plurals (among many other functions): Malay rumah "house", rumah-rumah "houses".
In pre-1972 Indonesian and Malaysian orthography, 2 was shorthand for the reduplication that forms plurals: orang "person", orang-orang or orang2 "people". This orthography has resurfaced widely in text messaging and other forms of electronic communication.
The Nama language uses reduplication to increase the force of a verb: go, "look;", go-go "examine with attention".
Chinese and Japanese do not make morphological use of reduplication, but some words are formed this way, often with a collective sense: rén "person", rénrén "everybody"; toki "time", tokidoki "sometimes, from time to time". The iteration mark can be used to indicate reduplication, although in Chinese the iteration mark is no longer used in standard writing and is often found only in calligraphy.
Indo-European languages formerly used reduplication to form a number of verb forms, especially in the preterite or perfect. In the older Indo-European languages, many such verbs survive:
spondeo, spopondi (Latin, "I vow, I vowed") (Greek, "I leave, I left") (Greek, "I see, I saw"; these Greek examples exhibit ablaut as well as reduplication) háitan, haíháit (Gothic, "to name, I named")
Those forms do not survive in Modern English but existed in its parent Germanic languages. Many verbs in the Indo-European languages exhibit reduplication in the present stem, rather than the perfect stem, often with a different vowel from that used for the perfect: Latin gigno, genui ("I beget, I begat") and Greek τίθημι, ἔθηκα, τέθηκα (I place, I placed, I have placed). Other Indo-European verbs used reduplication as a derivational process: compare Latin sto ("I stand") and sisto ("I remain"). All of those Indo-European inherited reduplicating forms are subject to reduction by other phonological laws.
Reduplication can be used to refer to the most prototypical instance of a word's meaning. In such a case, it is called contrastive focus reduplication. Finnish colloquial speech uses the process; nouns can be reduplicated to indicate genuinity, completeness, originality and being uncomplicated, as opposed to being fake, incomplete, complicated or fussy. It can be thought as compound word formation. For example, Söin jäätelöä ja karkkia, sekä tietysti ruokaruokaa. "I ate ice cream and candy, and of course food-food". Here, "food-food" is contrasted to "junk-food". One may say, "En ollut eilen koulussa, koska olin kipeä. Siis kipeäkipeä" ("I wasn't at school yesterday because I was sick. Sick-sick, that is"); that means that one was actually suffering from an illness instead of making up excuses, as usual.
ruoka "food", ruokaruoka "proper food", as opposed to snacks peli "game", pelipeli "complete game", as opposed to a mod puhelin "phone", puhelinpuhelin "phone for talking", as opposed to a pocket computer kauas "far away", kauaskauas "unquestionably far away"