The Japanese word 人生 meaning "Life" is composed of the kanji人 (read jin) meaning "person" and 生 (read sei) meaning "life; birth".
Japanese has a few words for "Life". jinsei refers to one's life and is specific. For example it is used when saying "My life has been good". It is not used in the abstract so one would not use jinsei in things like "gamble with one's life", "searching for life on mars" or "life insurance".