Sound symbolism is the nonarbitrary association between (speech) sound and meaning. The association may be iconic (i.e., based on resemblance, as with beep for a high electronic noise and zigzag for a repeated Z-shaped line), indexical (i.e., based on a causal relation, as with wow for admiration and phew for relief or fatigue), or systematic (i.e., based on conventional regularity). Sound symbolism is clearest in ideophones—onomatopoeia (i.e., sound-mimicking words) and other imitative sensory words that abound in numerous languages globally across continents (e.g., inura-banura, “indecisive” in Basque, and niko-niko, “smiling” in Japanese)—but is also found in ordinary words (e.g., sweep, yawn), revealing cross-linguistic phonological similarities of some basic vocabulary. It remains to be clarified what aspects of sound and what aspect of meaning is relevant to sound symbolism and how the sense of resemblance emerges in iconic sound symbolism. Sound symbolism can also help both children’s and adults’ word learning, and its role in the evolution of spoken language is actively debated.

History

Discussion about sound symbolism dates back at least to fifth century BCE. In Plato’s dialogue Cratylus, Socrates is asked whether words are natural or conventional. His examples of the naturalness of words include rho [r], which represents motion. Remarks on sound symbolism are also found in religious texts, such as the Upanishads (seventh century BCE; e.g., sibilants like śa /ɕɐ/ symbolizing the sky) and Shingon Buddhism (ninth century; e.g., /ba/ symbolizing water). On the other hand, de Saussure (1916) focused on the conventional aspect of words, proposing that the relationship between speech sound and meaning is essentially arbitrary. For example, trees have very different names across languages: arbor in Latin, Baum in German, and ki in Japanese.

Modern studies of sound symbolism started in the 1920s, when two key pseudoword experiments were reported. Sapir (1929) showed that people tend to think that mal is the name of a large table, whereas mil is the name of a small table. Köhler (1947) reported that baluma (or maluma) is associated with a rounded shape and takete with a spiky shape. However, sound symbolism has long been marginalized in linguistics under the strong influence of de Saussure's (1916) view (but see e.g., Jakobson & Waugh, 1979 ).

Ramachandran & Hubbard's (2001) replication of the maluma/takete effect, dubbed in their study the bouba/kiki effect, led to the revitalization of the study of sound symbolism and linguistic iconicity in general. Sound symbolism is an active area of research in cognitive science (Lockwood & Dingemanse, 2015) and is actively debated in the context of language acquisition and evolution [see Language Acquisition] (Ćwiek et al., 2022; Fort et al., 2018; Imai et al., 2008; Imai & Kita, 2014).

Core concepts

Sound symbolism has been studied using two major methods (Hinton et al., 1994). Linguists have compared the phonological distributions of basic words in numerous languages and found nonarbitrary sound–meaning correspondences, such as /n/ for “nose” (e.g., hana in Japanese, nú:snu in Nez Perce) and trilled /r/ for “rough” (e.g., raupja in Latvian, shirüün in Mongolian) (Erben Johansson et al., 2020; Winter et al., 2022). In contrast, psychologists have experimentally tested peoples’ sound-symbolic intuitions, typically using pseudowords or unknown foreign words in forced choice paradigms. Neuroscientists have also joined the investigation, using brain imaging or electroencephalography techniques, to uncover subtle, often unconscious sensitivity to sound symbolism or to identify the regions that play a key role for sound–meaning correspondences [see Neuroscience of Language] (Asano et al., 2015; Kanero et al., 2014). Developmental scientists endeavor to address when and how sensitivity to sound symbolism emerges and how this sensitivity plays a role in language acquisition (see Fort et al., 2018 for review).

Sound symbolism may arise from different motivations. Iconicity (i.e., perceived resemblance between form and meaning) is arguably the most common. For example, /r/ is associated with roughness, as the articulatory (e.g., the repetitive vibration of the tongue) or acoustic property (e.g., repetitive quick amplitude changes) of this consonant is perceived to resemble an uneven surface. Second, indexicality, especially a causal relation between form and meaning, may account for the association between /n/ and the nose: /n/ is a nasal consonant that involves the resonance of the nose. Third, systematicity (i.e., language-specific statistical regularity) resides in numerous cases of sound symbolism (Dingemanse et al., 2015). English words with the submorphemic element (called phonestheme) gl-, such as glance, glimmer, glisten, and glow, represent vision- or light-related meanings simply because of their common etymon *ghel- “to shine” in Proto–Indo–European (Firth, 1930). It should be noted that these three motivations often coincide, as in English sn- words for nose-related meanings, such as sneeze, sniff, snooze, and snore. They are both systematic (i.e., involving a phonestheme) and indexical (i.e., the nasal sound pointing to the nose).

Questions, controversies, and new developments

Levels of generalization

It is unclear what aspect of sound—e.g., /sn/ (phonestheme) vs. /n/ (segment) vs. nasal (phonetic feature) vs. frequency (acoustic attribute)—is associated with what aspect of meaning (e.g., spiky shape vs. acute angle vs. abrupt change) in sound symbolism (Ohala, 1984; Sidhu & Pexman, 2018). Moreover, there is an open question of how different sound-symbolic meanings of one sound (e.g., the smallness, brightness, and fastness of /i/) are related to each other (Winter et al., 2019).

Language specificity

It is unknown how language-specific sound symbolism arises. The existence of language-specific sound symbolism, such as /a/ for smallness in Korean ideophones, which is counter to the general intuition that /a/ maps onto largeness, suggests that the sense of iconicity may arise from language-specific systematicity.

Evolution of language

Sound symbolism may facilitate children’s and adults’ word learning [see Word Learning]. It is an open question whether sound symbolism also helped in the creation and evolution of spoken language.

Broader connections

The cognitive and neural mechanisms for sound symbolism need systematic comparisons with other phenomena, such as iconicity in spoken and signed language, crossmodal correspondence, and synesthesia (see Cuskley & Kirby, 2013).

Sound Symbolism