take someone's breath away
1. Lit. to cause someone to be out of breath due to a shock or hard exercise. Running this fast takes my breath away. Mary frightened me and took my breath away.
2. Fig. to overwhelm someone with beauty or grandeur; to surprise or astound someone. The magnificent painting took my breath away. Ann looked so beautiful that she took my breath away.
take one's breath away
Astonish or shock one, with pleasure, surprise, or some other emotion. For example, That beautiful display just takes my breath away. This idiom alludes to the way one holds one's breath when overcome with sudden emotion. [Mid-1800s]
take (one's) breath away
To put into a state of awe or shock.
take one's breath away, to
To astound. This expression is pure hyperbole: one is so flabbergasted that one stops breathing. (The same idea is conveyed in the adjective breathtaking.) In the mid-nineteenth century Robert Browning used the term in Dramatis Personae (1864): “He never saw . . . what was able to take his breath away.”