at a rate of knots

Prepositional phrase

UK informal

(UK, informal) Quickly; rapidly; fast.

Japanese Meaning

非常に速い速度で / 急速に / 素早く

The old printer chewed through the stack of forms at a rate of knots, surprising everyone in the office.

古いプリンターは書類の山をものすごい速さで処理し、オフィスの皆を驚かせた。

Sense（1）

(UK, informal) Quickly; rapidly; fast.