Some languages have a grammatical class just for words that sound like what they mean

In languages like Japanese, Korean, and many across West Africa, ideophones form a distinct part of speech: vivid words like Japanese 'kirakira' (glittering) or 'dokidoki' (heart pounding) that evoke a sensation or motion through their sound. Unlike English onomatopoeia, which mostly covers noises, ideophones can vividly depict textures, emotions and movement, and speakers treat them as a real, productive grammatical class rather than playful exceptions.

— F.K. Erhard Voeltz, Christa Kilian-Hatz (eds.), Ideophones — 2001
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