adjective
Definition: Feeling unwell or having a disease; also used to describe something that is unhealthy or in poor condition.
Example: She stayed home from school because she felt sick.
noun
Definition: People who are ill or unwell, often referred to collectively.
Example: The hospital is providing care for the sick during the flu season.
verb
Definition: To cause someone or something to vomit or to set a dog on someone.
Example: He sicked the dog on the intruder.