Precaution (noun)

1. A measure taken in advance to prevent something undesirable from happening.
2. A measure taken to avoid potential danger or harm.

Origin:

From middle french précaution, from précautionner ("to take precautions"), from latin praecautus ("foresighted"), from prae ("before") + cautus ("cautiou.s")

Examples:

1. As a precaution, he always wore a helmet when riding his bike.
2. The government issued a warning as a precaution against the spread of the disease.
3. She took the precaution of keeping her phone charged at all times.
4. As a precaution, the company decided to recall the product.
5. He took every precaution to protect his family from the storm.