guardian angel

American  

noun

1. an angel believed to protect a particular person, as from danger or error.

2. a person who looks after or is concerned with the welfare of another.

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Etymology

Origin of guardian angel

First recorded in 1625–35

Example Sentences

Artificial intelligence was supposed to be the stock market’s guardian angel, but this past week, investors were grappling with the possibility that it has become Frankenstein’s monster.

From Barron's

Artificial intelligence was supposed to be the stock market’s guardian angel, but this past week, investors were grappling with the possibility that it has become Frankenstein’s monster.

From Barron's

She is at once guardian angel and angel of death, watching over hallowed ground while carrying a tool of invasive modernity with her.

From The Wall Street Journal

What’s it like to be the guardian angel of people who text while driving?

From The Wall Street Journal

"They sent me a guardian angel that day," he said.

From BBC