Comparing semantic and phonetic similarities between Turkish and Japanese onomatopoeia.

Sound symbolism research reveals a non-arbitrary relationship between phonetics and meaning, demonstrating strong associations between consonant sounds and perceived shape, size, or material. Onomatopoeias, a subset of sound-symbolic expressions, directly imitate the sound they describe. Previous evidence suggests that onomatopoeias encode sound-symbolic cues, even across unfamiliar languages, but no specific research has been done specifically on material-related sound symbolism. To examine how the phonetic and semantic features of onomatopoeic words influence material perception, we conducted a semantic differentiation task with Turkish-speaking participants (N = 28) unfamiliar with Japanese. Stimuli consisted of three-word sets: 14 Turkish words, 14 semantically similar Japanese words, and 14 phonetically similar Japanese words. For example, the Turkish word mır mır (a humming sound) shares a similar meaning with the Japanese word hiso hiso (speaking in a low or hushed tone), and shows phonetic similarity to the Japanese word miri miri (slowly tearing or stretching something tightly). Participants rated each word on seven adjective pairs: (1) flat-bumpy, (2) warm-cold, (3) wet-dry, (4) light-heavy, (5) smooth-rough, (6) slippery-sticky, and (7) granular-whole. Equivalence testing further indicated that phonetically similar pairs more frequently fell within predefined equivalence bounds and showed smaller deviations across adjective dimensions. Multidimensional scaling additionally revealed smaller perceptual distances between Turkish words and their phonetically similar Japanese counterparts. Together, these findings suggest that phonetic similarity contributes more strongly than semantic similarity to cross-linguistic material-related judgements. Furthermore, the results highlight distinctive sound patterns shared by Japanese and Turkish onomatopoeias, suggesting the existence of universal phonetic markers for material-related sound symbolism.