In English, round and spiky objects tend to have “round” and “spiky” sounds

Many of us are familiar with the "bouba/kiki", or "maluma/takete" effect — that we tend to pair round, blobby shapes with the words "bouba" or "maluma" and spiky shapes with "kiki" or "takete". These findings hold for speakers of many different languages and ages, and various explanations for the effect have been proposed.

But these studies have almost exclusively used made-up words (like these four), note the authors of a new paper in Psychonomic Bulletin & Review, who have found that the effect is also at play in the English language. That is, the components of made-up words that we commonly pair with a round shape tend also to be found in nouns that refer to actual round objects, and the same for spiky sounds and objects.

David M Sidhu, now at University College, London, and colleagues recruited 171 student participants in Canada. Each person was presented with 100 sets of six concrete nouns, and for each set, had to choose the two nouns that they felt referred to the "most round" and "most spiky" objects — so, for example, they had to pick the most-round and most-spiky objects from "unicycle", "moon", "balcony", "pyramid", "jet" and "driller". From these results, the researchers generated a spiky/round rating for each word. (The top five "roundest" in order were : softball, ball, olive, pea and globe, while spike, fork, porcupine and scalpel led the "spikiest" object list.)

The team then looked at the phonemes, or distinct "units" of sound, which made up these nouns. They compared these results with those from earlier studies that have investigated which phonemes in made-up words are generally associated with roundness or spikiness.

Almost all of the phonemes previously associated with roundness were indeed present in the real words that participants identified as referring to round objects, and the same for spikiness. So the sounds u as in "up", m, oo as in boot and b were more common in nouns that referred to round objects, while the sounds k, t and i as in "ship" were more common in nouns that referred to spiky objects. "Our main finding was that many of the associations between phonemes and shapes found in laboratory tasks are attested in the pairing between sound and meaning in English," the team writes.

There were a few unexpected findings. For example, in this study, in contrast to some earlier ones involving made-up words, s and sh were more common in words for spiky objects. However, this result does fit with work linking certain phonemes to greater or lesser emotional arousal. We tend to perceive words with hissing sounds as being higher in emotional arousal — which is also linked to spikiness. The researchers also note that these phonemes, along with other consonants common in words for spiky objects, require the involvement of the tongue, whereas m, b, etc are made just with the lips.

This work contributes to the argument that (in addition to cases of onomatopoeia) there is at least some relationship between the sound of words in English and what they refer to. This isn't a powerful relationship; as the researchers themselves stress: "Many other factors play larger roles in the form of language." Still, the work does reveal some consistent round/spiky patterns in real English words, which seems to be a first in almost 100 years of research into this effect.

Further reading

– Sound symbolism shapes the English language: The maluma/takete effect in English nouns

About the author

Emma Young (@EmmaELYoung) is a staff writer at BPS Research Digest