要害

yàohài
  1. vital part
  2. (fig.) key point
  3. crucial

CEDICT

Entry Composition

1 要 yào
  1. to want; to need; to ask for
  2. will; shall; about to
  3. need to; should
  4. if (same as 要是 yàoshi)
  5. (bound form) important
2 害 hài
  1. to do harm to
  2. to cause trouble to
  3. harm
  4. evil
  5. calamity