+12 = 15 

ㄔㄥˊchéng

  1. 靜止清澈南朝·謝朓三山京邑。」·陳子昂大夫〉:翠微列坐青山磐石。」

+12 = 15 

ㄉㄥˋdèng

  1. 使沉澱清澈。」

surname Cheng, clear, limpid, to clarify, to purify, (of liquid)​ to settle, to become clear
limpide, clarifié, décanter, clarifier