毕世 (bì shì) is a formal literary term meaning 'throughout one's entire life' or 'lifetime.' The character 毕 (bì) means 'to complete' or 'to finish,' and 世 (shì) means 'generation' or 'lifetime'; together, they convey the idea of something extending to the very end of one’s life. It emphasizes totality and finality — not just 'a long time,' but the full span from birth to death.

This word is rarely used in casual speech; it appears mainly in classical texts, formal writing, obituaries, biographies, or solemn declarations. It often modifies nouns like '事业' (career), '追求' (pursuit), or '心愿' (wish), and functions as a time noun phrase that typically precedes the verb or appears after prepositions like '为' (for) or '以' (with). Because of its elevated register, learners should avoid using it in everyday conversation or informal emails.