1. To suffer from a disease or a health problem which makes you unable to work or to live normally. Used particularly for problems which happen suddenly or last for only a short time. English = (be) sick, (be) ill.
2. To become or get sick, to fall ill.
3. Of acts, stories, or jokes, to deal with death, cruelty, or suffering in a frivolous way. English = (be) sick, (be) disgusting, (be) distasteful.