What is Anguish?

Legal Definition
Anguish is a term used in philosophy, often as a translation from the Latin for angst. It is a paramount feature of existentialist philosophy, in which anguish is often understood as the experience of an utterly free being in a world with zero absolutes (existential despair). In the theology of Kierkegaard, it refers to a being with total free will who is in a constant state of spiritual fear that his freedom will lead him to fall short of the standards that God has laid out for them.
-- Wikipedia
Legal Definition
Great or extreme pain, agony or distress, either of body or mind; but, as used in law, particularly mental suffering or distress of great intensity. Cook v. Railway Co., 19 Mo. App. 334.
-- Black's Law Dictionary
Legal Definition
Extreme mental or physical pain.
-- Ballentine's Law Dictionary