Angst is a feeling of anxiety and frustration that isn't specific. People often feel angst about the state of the world, or about the state of their homework.
Angst is anxiety that is mixed with frustration and negativity. Angst often doesn’t have a specific target: people feel angst in general. Teenagers are known for their angst, which is shown when they act miserable about nothing in particular. Often, angst refers to philosophical displeasure with world events or personal freedom. An angst-filled person is dissatisfied and unhappy.