sickness
"Sickness" is a word you will encounter very often in everyday English. It has a few closely related meanings, all connected to the idea of not feeling well or something being deeply wrong — either physically or emotionally.
Sometimes 'sickness' refers specifically to that horrible feeling in your stomach when you feel like you are going to vomit. You will often hear phrases like 'morning sickness' (nausea during pregnancy) or 'travel sickness' (feeling sick on a car or boat).
everyday language / health · Modern, widely used
When something is so wrong, cruel, or shocking that it makes you feel deeply disturbed — not physically, but emotionally — you can describe that reaction as sickness. It is a figurative way of saying something feels truly wrong to you.
everyday language / emotional expression · Modern, widely used · figurative
You can also use 'sickness' to describe a deep, widespread problem in a group, organization, or society — as if the whole system were ill. This is a powerful, figurative use of the word.
social commentary / politics / literature · Modern, used in formal and written contexts · figurative