unwell

Unwell is an adjective used to describe a state of not feeling well, typically implying mild discomfort or a temporary health issue rather than a diagnosed disease. It is common in British English to describe general malaise or non-specific symptoms such as tiredness, nausea, dizziness, or a slight fever. In American English, speakers more often say "sick" or "not feeling well," but unwell is understood and used in formal or cautious contexts, including healthcare settings.

The term derives from the negation of "well" with the prefix un-, historically meaning lacking good health. It can be used with be, look, or feel as the linking verb: "I am feeling unwell," "She looks a bit unwell."

In medical contexts, unwell may signal a transient or non-specific condition; it does not denote a specific diagnosis. Persistent, severe, or unusual symptoms—such as high fever, chest pain, or confusion—warrant professional evaluation. Causes of an unwell feeling range from infections and dehydration to stress, fatigue, motion sickness, or pregnancy-related discomfort.

Related terms include ill, sick, and under the weather. Unwell is generally milder and less precise than "ill" or "disease," and may be preferred in polite or cautious discourse, particularly when the exact cause is unknown or not disclosed.