Heart-stopping (adjective)

1. Extremely exciting or dramatic.
2. Extremely beautiful or attractive.
3. Extremely frightening or disturbing.

Origin:

The phrase likely originated in the early 20th century, and likely comes from the idea of something so exciting or dramatic that it causes one's heart to literally stop.

Examples:

1. The acrobat's death-defying stunts were heart-stopping.
2. The sight of the Grand Canyon at sunset was heart-stopping.
3. The horror movie was so heart-stopping that I had to look away.