Feeling weak, dizzy and not quite steady — the world moves a bit, your head is not clear, and you might need to sit down. It is the feeling after you stand up too fast, after you give blood, after a bang on the head, after medicine that is too strong, or after too much alcohol. Two things make it different from plain "dizzy". First, woozy covers the whole body, not just the head: dizzy is the spinning, woozy is the spinning plus the weakness plus the slight sickness in your stomach. Second, woozy is gentle and informal — a friendly, everyday word, the one you use with family, not the one a doctor writes in your file. A doctor says "the patient reported dizziness"; you say "I feel a bit woozy". Because it is soft, English speakers often use it to make something serious sound smaller and more bearable, which is worth noticing: someone saying "I went a bit woozy" may actually have nearly fainted. People also stretch it away from the body to talk about thinking — "a woozy argument" is one that is not clear, that wanders. That use is not common; the body use is the main one.