1. A friendly expression used to say goodbye or to greet someone.
Usage: British informal; often used in casual or lighthearted contexts
2. An exclamation used to express good wishes or encouragement.
Usage: British informal; dated

1. A small ring-shaped breakfast cereal.
Usage: trademark; often used in plural

Examples

• Cheerio! I'll see you next week.
• She waved and called out cheerio as the train pulled away.
• Cheerio, mate! Have a great day.
• The kids poured cheerios into their bowls for breakfast.
• He raised his glass and said cheerio to the happy couple.