The word 几乎 is formed through the fusion of two classical Chinese elements: the character 几, which originally conveys the idea of being close to a point, subtle, or nearly reaching a state, and the character 乎, a classical grammatical particle that here functions to extend and finalize that notion, turning it into a complete abstract concept. Together, they create a single unit meaning "almost" or "nearly", where the first character provides the core semantic idea of proximity and the second character completes and grammaticalizes it into a standalone adverb. This formation is a classic example of lexicalization, where a frequently used phrase from classical Chinese solidified over time into a fixed, inseparable modern word.