Used in formal, literary, or poetic contexts to express something lasting through all ages or for eternity. Often appears in set phrases like 万世不易 (eternally unchanging) or 万世の後 (for all posterity).
Compound of 万 (ten thousand, myriad) and 世 (generation, age), literally 'ten thousand generations'. The exact historical derivation is uncertain, but the spelling is conventionally associated with the meaning of eternity or all ages.
