a precautionary measure warding off impending danger or damage or injury etc.
"he put an ice pack on the injury as a precaution"
"an insurance policy is a good safeguard"
"we let our guard down"
a document or escort providing safe passage through a region especially in time of war
"The diplomat carried a special safeguard that guaranteed his safe passage through the war-torn border region."
Something that serves as a guard or protection; a defense.
"The old stone wall served as an effective safeguard against flooding during the storm."
In plain English: A safeguard is something you keep to stop bad things from happening.
"The bank's data backup serves as an important safeguard against losing customer information."
Usage: Use safeguard as a noun when referring to specific measures taken to ensure safety, such as "security safeguards." Avoid using the verb form in casual conversation where simpler terms like "protect" would be more natural.
make safe
"The engineer installed new brakes to safeguard the passengers from falling off the cliff."
escort safely
"The bodyguard's primary duty is to safeguard the celebrity as she walks through the crowded city streets."
To protect, to keep safe.
"The new security system was installed to safeguard the museum's priceless artifacts from theft."
The word safeguard comes from the phrase salve garde in Old French, which literally meant "safe guard." It entered English through Middle French and retained its original sense of protecting something from harm.