What is the defination of ill or sick based on?

It describes short-term diseases or ailments, like the flu, and is commonly used to refer to a feeling of nausea. Like sick, ill also refers to a feeling of nausea. Two common combinations of ill are "ill health" and "mentally ill.

HOPE THIS HELPS!! :)

You dont feel well I guess.

the psychologist would claim that the research results were significant.