严谨

嚴謹
yánjǐn
  1. rigorous; strict; careful
  2. (of writing) well organized; meticulous

CEDICT

Entry Composition

1 严 yán
  1. tight (closely sealed)
  2. stern
  3. strict
  4. rigorous
  5. severe
  6. father
2 谨 jǐn
  1. cautious
  2. careful
  3. solemnly
  4. sincerely (formal)