The Japanese language has a large inventory of sound symbolic or mimetic words, known in linguistics as ideophones. Such words are found in written as well as spoken Japanese. Known popularly as onomatopoeia, these words do not just imitate sounds but also cover a much wider range of meanings; indeed, many sound-symbolic words in Japanese are for things that make no noise originally, most clearly demonstrated by, not to be confused with the religion Shintō.
The sound-symbolic words of Japanese can be classified into four main categories:
These divisions are not always drawn: sound-symbolism may be referred to generally as onomatopoeia (though strictly this refers to imitative sounds, phonomimes); phonomimes may not be distinguished as animate/inanimate, both being referred to as giseigo; and both phenomimes and psychomimes may be referred to as gitaigo.
In Japanese grammar, sound-symbolic words primarily function as adverbs, though they can also function as verbs (verbal adverbs) with the auxiliary verb, often in the continuous/progressive form, and as adjectives (participle) with the perfective form of this verb . Just like ideophones in many other languages, they are often introduced by a quotative complementizer . Most sound symbolic words can be applied to only a handful of verbs or adjectives. In the examples below, the classified verb or adjective is placed in square brackets.
| Sound Symbolism | Meaning | |
|---|---|---|
| jirojiro (to) [miru] Japanese: じろじろ(と)[見る] | [see] intently (= stare) | |
| kirakira (to) [hikaru] Japanese: きらきら(と)[光る] | [shine] sparklingly | |
| giragira (to) [hikaru] Japanese: ぎらぎら(と)[光る] | [shine] dazzlingly | |
| doki doki [suru]* Japanese: どきどき[する]* | with a throbbing heart* | |
| guzu guzu [suru] Japanese: ぐずぐず[する] | procrastinating or dawdling (suru not optional) | |
| shiin to [suru] Japanese: しいんと[する] | [be (lit. do)] quiet (suru not optional) | |
| pinpin [shite iru] Japanese: ぴんぴん[している] | [be (lit. do)] lively (shite iru not optional) | |
| Japanese: よぼよぼに[なる] yoboyobo ni [naru] | [become] wobbly-legged (from age) |
* Unlike the other examples, doki doki is an onomatopoeic word and mimics the sound of two heartbeats.
In their Dictionary of Basic Japanese Grammar, Seiichi Makino and Michio Tsutsui point out several other types of sound symbolism in Japanese, that relate phonemes and psychological states. For example, the nasal sound pronounced as /[n]/ gives a more personal and speaker-oriented impression than the velars pronounced as /[k]/ and pronounced as /[ɡ]/; this contrast can be easily noticed in pairs of synonyms such as and which both mean because, but with the first being perceived as more subjective. This relationship can be correlated with phenomimes containing nasal and velar sounds: While phenomimes containing nasals give the feeling of tactuality and warmth, those containing velars tend to represent hardness, sharpness, and suddenness.
Similarly, i-type adjectives that contain the fricative pronounced as /link/ in the group shi tend to represent human emotive states, such as in the words,,, and . This too is correlated with those phenomimes and psychomimes containing the same fricative sound, for example and .
The use of the gemination can create a more emphatic or emotive version of a word, as in the following pairs of words:,,, and many others.