Compounds of 孤

• 戦災孤児
  (n) war orphan
• 天涯孤独
  (n) a person without a single relative
• 狷介孤高
  (n,adj-na) stubborn and aloof
• 鰥寡孤独
  (n) with no one upon whom to depend
  utter loneliness
  the lonely and the helpless
  people who have no kith or kin
• 幼にして孤となる
  (exp) to be orphaned in one's babyhood