先例

xiānlì
precedent

CEDICT

Entry Composition

1 先 xiān
  1. beforehand; first; earlier
  2. at first; originally
  3. for the time being; for now
  4. (prefix) my late (in referring to deceased relatives older than oneself)
2 例 lì
  1. example
  2. precedent
  3. rule
  4. case
  5. instance