1. lacking confidence in oneself; uncertain about one’s abilities or worth
2. not safe or protected; vulnerable to danger or attack
3. not firmly fixed or stable; likely to fail or give way

Examples

• She felt insecure about her presentation skills.
• The insecure teenager worried constantly about what others thought of him.
• The building’s insecure foundation made it dangerous during earthquakes.
• Their insecure financial situation kept them awake at night.
• The ladder felt insecure against the wall.
• He was insecure about his accent when speaking English.
• The insecure network connection kept dropping calls.