The word 克拉 (kèlā) is a phonetic borrowing, formed by selecting two existing Chinese characters whose combined pronunciation closely approximates the sound of the foreign word it represents, in this case, the unit of mass "carat" (from the Greek "keration"). The characters 克 and 拉 were chosen not for their individual meanings ("to overcome" and "to pull", respectively), but solely for their sounds, which together mimic "carat". This created a dedicated term for measuring gemstone weight, now fully integrated into the language.