1. in a way that involves risk of harm or injury
2. to an extent that threatens something undesirable

Examples

• He was driving dangerously fast on the icy road.
• The building is dangerously close to collapse.
• She leaned dangerously over the cliff edge.
• The patient’s fever was dangerously high.
• The company is dangerously low on funds.
• They were skating dangerously on thin ice.