Abstract: Phonosemantic iconicity, the inherent association between sound and meaning in language, has been subject to criticism or even denial among linguists who adhere to the arbitrariness of linguistic signs. Taking the concept of ‘LIGHT’ as an example, this study investigates the role of phonosemantic iconicity in concept naming in English and Chinese. Results show that: 1) in both English and Chinese, there exist phonetic forms smaller than morphemes that exhibit phonosemantic iconicity. For instance, the ‘LIGHT’ concept, together with its extended concepts, is iconically associated with the phonestheme /gl/ in English words and the phonetic radical “昜/yang” in Chinese characters. 2) Based on the psychological perception effect generated through the combination of their places of articulation, manners of articulation, and various acoustic features, sounds can convey meanings, and these meanings highlight some particular features that closely relate to the etymology of words. 3) Phonosemantic iconicity, to some extent, contributes to both the initial word creation and derived word formation processes in English and Chinese. In the initial stage, ancient people create words by imitating sounds through movements of lips, tongue, and breath, thereby illustrating a certain degree of iconicity. In the derived stage, similar or related concepts may be represented by identical or similar sounds through metaphor and metonymy, which results in a relatively systematic relationship between meaning and sound in the lexicons of both English and Chinese.