謎底

谜底
mídǐ
answer to a riddle

CEDICT

Entry Composition

1 謎 mí riddle
2 底 dǐ
  1. bottom; base
  2. background; foundation
  3. copy (of a manuscript or receipt etc) kept as a record
  4. (suffix) end of a year or month
  5. (math.) radix; base (abbr. for 底數 dǐshù)