Defense vs Security

When to use each in English, with meaning, register, and examples.

 DefenseSecurity
MeaningProtection from harm or danger.Protection from danger or harm.
CEFR levelB2B1
Part of speechnounnoun
Usage notesUsed in legal, sports, and military contexts. Avoid using in casual conversations that don't involve conflict or protection.Commonly used in contexts related to safety, such as cybersecurity, personal safety, or physical safety. It is appropriate in both formal and informal situations.

Frequently asked questions: Defense vs Security

What's the difference between "Defense" and "Security"?

"Defense" means: Protection from harm or danger. "Security" means: Protection from danger or harm.

When should I use "Defense" and "Security"?

They can all be used in everyday English.

Are "Defense" and "Security" the same CEFR level?

"Defense" is at B2, "Security" is at B1 on the CEFR scale.

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