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Related to watch out: look out
be aware They say a storm is coming, so watch out and don't take any chances.Related vocabulary: look out
Usage notes: sometimes used as an order: Andy saw the car coming toward them, and yelled, â€œWatch out!â€
1. To be careful or on the alert; take care: If you don't watch out, you'll fall on the ice.
2. watch out for To be careful of some danger: Watch out for falling rocks!