Angst /aŋst/ noun 

Definition: Angst can be defined as having major anxiety or fear related to situations or circumstances in general, not typically focused on a single aspect. It often describes anxiety based on the state of the entire world in general or conditions of the human mind.

Etymology: The word angst is derived from Danish, Norwegian, German and Dutch origin, which is exactly the same as the word in English. It was introduced in the 19th century by Kierkegaard and Freud, who translated the word to have an English definition. In English, it is used to describe having deep-seated fear or anxiety within one’s own mind. It is a personal state of being.

In a Sentence

He noticed signs of inner angst whilst looking into her beautiful, large hazel brown eyes. This is when he knew that she indeed had a deep-seated angst within her, which dulled the sparkle of her eyes.

The moment he turned 40, a wave of existential angst flowed through his body.

The riots and looting had been causing her great angst.

Synonyms 

Anxiety, Fear, Dread

Antonyms 

Calmness, Composure, Ease