indefensible

/ˌɪndɪˈfɛnsəbəl/
adjective
  1. Impossible to defend or protect from attack.
    • The old fort was in an indefensible position, surrounded by higher hills.
    • Without a strong navy, the island nation's coastline was nearly indefensible.
    • The goalkeeper left the goal indefensible when he ran out too far.
  2. Impossible to justify or excuse; morally unacceptable.
    • Bullying is an indefensible behavior that schools must address.
    • It is indefensible to ignore the needs of the poor in our community.
    • The politician's lies were indefensible, and he lost the election.