The word "嗡嗡" is a classic example of a reduplicated onomatopoeia in Chinese, formed by repeating the single character "嗡" (*wēng*), which itself is a phonetic symbol mimicking a droning or buzzing sound. This structural pattern, known as the "AA式," serves to intensify and elongate the auditory impression, creating a vivid sense of a continuous, resonant hum. As a result, "嗡嗡" is primarily used to describe the persistent buzzing of insects like bees or flies, or the low, vibrating noise of machinery, effectively capturing the sustained and immersive quality of the sound through its repetitive form.