secure
Safe from danger or harm, or made safe and protected.
Secure means safe from danger, harm, or loss. When you put your bike in a secure location, you've locked it somewhere thieves can't easily steal it. A secure building has strong locks, alarms, and maybe guards to keep unwanted people out. Your passwords should be secure so hackers can't break into your accounts.
The word can also describe emotional safety and confidence. A child who feels secure knows their parents love them and will take care of them. When you feel secure in your friendship with someone, you trust they won't suddenly abandon you. A student who feels secure in their math skills approaches new problems with confidence rather than fear.
To secure something (as a verb) means to make it safe or to obtain it. You might secure a tent with stakes so it won't blow away, or secure tickets to a concert you've been wanting to see. A ship's captain secures the cargo before sailing into rough waters. When a team secures a victory, they've locked it in, making sure the win can't slip away.
Security is the state of being secure. A security guard protects a building. Security measures protect information, belongings, or people from threats.