at\ a\ blow

at\ a\ blow
• at a blow
• at a stroke
• at one stroke
adv. phr.
Immediately; suddenly; with one quick or forceful action.

The pirates captured the ship and captured a ton of gold at a blow.

A thousand men lost their jobs at a stroke when the factory closed.

All the prisoners escaped at one stroke.

Compare: at once, at one time

Словарь американских идиом. — СПб., Изд-во "Лань". . 1997.