積鬱

pent-up frustrations / sth that has accumulated in one's mind for a long time

(of gloomy thoughts etc) to smolder; to accumulate in one's mind / accumulated anxiety

to amass / to accumulate / to store / measured quantity (such as area of volume) / product (the result of multiplication) / to integrate (math.) / to solve (or integrate) an ordinary differential equation (math.) / old / long-standing

surname Yu

dense (growth) / melancholy

(bound form) (of vegetation) lush; luxuriant / (bound form) melancholy; depressed