What is the meaning of 常?

always, constantly, consistently

a traditional Japanese unit of length, equal to one 丈(じょう) (jō, roughly three meters) and three 尺(しゃく) (shaku, roughly one foot or thirty centimeters)

a traditional Japanese unit of measure for the length of cut cloth, equal to one 丈(じょう) (jō, roughly three meters) and three 尺(しゃく) (shaku, roughly one foot or thirty centimeters)

a traditional Japanese unit of measure for the area of an agricultural field or paddy, equal initially to 360 歩(ぶ) (bu, around 1190 square meters), later reduced to 300 歩(ぶ) (bu) or 坪(つぼ) (tsubo, almost 992 square meters)

eternal, permanent, consistent

normal, everyday, regular, usual, ordinary

constant, continuous, always

usual, ordinary, everyday, normal

custom, habit, practice

eternal, forever, unchanging, everlasting

permanent, eternal

usual, ordinary

permanence, eternity

Source: wiktionary.org