Describes a sudden, sharp movement or change, often implying a jolt or abrupt drop. Common with verbs like 落ちる, 下がる, 止まる.
エレベーターががくんと止まった。
The elevator stopped with a jerk.
気温ががくんと下がった。
The temperature dropped suddenly.
The bus came to a sudden jerking stop with the emergency brake.
今月の売り上げががくんと下がった。
This month's sales dropped sharply.
The train stopped suddenly and my body jerked forward.
Mimetic word derived from the sound or sensation of a sudden, jerky movement. The exact origin is uncertain.