Ideophones are words that evoke an idea in sound, often a vivid impression of certain sensations or sensory perceptions, e.g. sound, movement, color, shape, or action. Ideophones are found in many of the world's languages, though they are claimed to be relatively uncommon in Western languages. The word class of ideophones is sometimes called phonosemantic to indicate that it is not a grammatical word class in the traditional sense of the word (like 'verb' or 'noun'), but rather a lexical class based on the special relation between form and meaning exhibited by ideophones. In the discipline of linguistics, ideophones have long been overlooked or treated as mysterious words, though a recent surge of interest in sound symbolism, iconicity and linguistic diversity has brought them renewed attention.
An often-cited definition of the notion of ideophone is the following by Clement Martyn Doke 
- ‘A vivid representation of an idea in sound. A word, often onomatopoeic, which describes a predicate, qualificative or adverb in respect to manner, color, sound, smell, action, state or intensity.’
Ideophones evoke sensory events. A well known instance of ideophones are onomatopoeic words – words that imitate the sound (of the event) they refer to. Some ideophones may be derived from onomatopoeic notions. A case in point is the English ideophonic verb to tinkle, which is likely to be derived from an imitation of a brief metallic sound.
Ideophones are often characterized as iconic or sound-symbolic words, meaning that there can be a resemblance between their form and their meaning. For instance, in West-African languages, voiced consonants and low tone in ideophones are often connected to large and heavy meanings, whereas voiceless consonants and high tones tend to relate to small and light things. Reduplication figures quite prominently in ideophones, often conveying a sense of repetition or plurality present in the evoked event. The iconicity of ideophones is shown by the fact that people can guess the meanings of ideophones from various languages at a level above chance. However, not everything about the form of ideophones directly relates to their meaning; they contain a degree of arbitrariness just like other parts of the vocabulary.
The grammatical function of ideophones varies by language. In some languages (e.g. Welayta, Yir-Yiront, Finnish), they form a separate word classes, while in others, they pervade a number of different word classes (e.g. Mundang, Ewe, Sotho), Hausa.
Despite this diversity, ideophones show a number of robust grammatical regularities across languages. Two particularly common kinds of constructions in which ideophones occur is (i) in collocation with another content word, usually a verb and (ii) on their own as an independent depiction of an event. Another common feature across languages, especially in narrative contexts, is the possibility of introducing ideophones via a verbum dicendi, grammatically often via a quotative complementizer, as in the following example from Ewe:
- É-ƒú así nu bé bóbóbó (3SG-strike hand mouth like IDEOPHONE) ‘S/he raised an alarm and went “bóbóbó”.’ 
Sometimes ideophones can form a complete utterance on their own, as in English "ta-da!" or Japanese jaan (ジャーン?, ta-da). However, ideophones often function as parts of sentences, with various grammatical functions such as adjectives or adverbs, as in Japanese hatto (はっと?, with a start, (be) startled), which is an adverb and verbal noun, as in hatto ki ga tsuita (はっと気が付いた?, I noticed with a start) or hatto shita (はっとした?, I was startled). Even when they form part of another utterance, however, ideophones tend to stand out as special: they are 'linguistic rebels', often produced with higher intonation and expressive lenthening, and set off from the rest of the utterance by a brief pause.
Languages also differ in the context in which ideophones are used. In some languages, ideophones are primarily used in spoken language (e.g. narrative contexts) and are rarely encountered in written language. In other languages (e.g. Ewe, Japanese), ideophones can be freely used in all registers. In general, however, ideophones tend to occur more extensively in spoken language because of their expressive or dramaturgic function.
- boing; the sound of a spring being released
- boom; the sound of an explosion
- bang; the sound of a gunshot
- bling-bling; glitter, sparkle
- doh!; expressing the feeling of having been tricked or a feeling of frustration
- huh!; expressing that one is not impressed
- uh-oh!; expressing the feeling that something unfortunate is about to happen
- ouch! expressing sudden pain
- phwoar!; expressing that a person is attractive
- pitter-patter; the sound of rain drops
- swish; the sound of swift movement
- splish-splash; the sound of water splashing
- ta-daa!; the sound of a fanfare
- thud; the sound of something heavy falling on the ground
- tick-tock; the sound of time passing
- tsk tsk tsk or tut tut!; the sound of disapproval
- twinkle; the glow of something sparkling or shiny
- whoops! or oops!; said when a person realises he has made a mistake
- wow!; expressing admiration or surprise
The Japanese language has hundreds if not thousands of such constructions. The constructions are quite metrical 2-2, or 3-3, where mora plays a role in the symmetry. The second item of the reduplication may become voiced if phonological conditions allow, rendaku. These original or native expressions are used extensively in daily conversations as well as in the written language.
- ドキドキ doki doki — heartbeat -> excitement
- キラキラ kira kira — glitter
- シーン shiin — silence
- ニコニコ niko niko — smile
- Sound symbolism (phonosemantics)
- Japanese sound symbolism
- Nuckolls 2004
- Voeltz and Kilian-Hatz 2001:2
- Imai & Kita 2014, Dingemanse et al. 2015
- Doke 1935 as cited in Voeltz & Kilian-Hatz 2001
- Westermann 1927
- Watson in Voeltz & Kilian-Hatz 2001
- Iwasaki et al. 2007, Dingemanse et al. 2015
- Voeltz & Kilian-Hatz 2001
- Childs, 1994:181
- Ameka in Voeltz & Kilian-Hatz 2001
- Diffloth 1972
- Kunene in Voeltz & Kilian-Hatz 2001
- Noss in Voeltz & Kilian-Hatz 2001
- Kunene in Voeltz & Kilian-Hatz 2001
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