约
定
俗
成
y
u
ē
d
ì
n
g
s
ú
c
h
é
n
g
Definitions
1. established by popular usage (idiom)
2. common usage agreement
3. customary convention
Components
约定
yuē dìng
–
to agree on sth (after discussion)
俗
sú
–
custom
成
Chéng
–
surname Cheng