1. in a way that is safe from danger, harm, or loss
2. in a way that is firmly fixed or fastened
3. with confidence and without worry

Examples

• The documents were stored securely in a fireproof safe.
• Make sure the ladder is positioned securely before climbing.
• She fastened her seatbelt securely before the flight.
• The password protects your account securely from hackers.
• He slept securely knowing the doors were locked.
• The tent was securely anchored to withstand strong winds.
• They invested their money securely in government bonds.