日積月累

Sun; day; daytime; the earth's rotation period; daily; a specific day; Japan (abbr.)

To accumulate or store up; to amass; the result of multiplication in math; long-term accumulation; constipation or indigestion in TCM.

Moon; month; monthly; moonlight; a surname; a radical component.

Tired or weary; to strain or wear out; to work hard; to accumulate or involve; continuous or repeated; rope or to bind.