勢い

いきおい

force, vigor, momentum

JLPT N3

Character Breakdown

Understanding 勢い (いきおい)

勢い refers to the force, momentum, or vigor behind an action or event. It can describe physical energy, emotional drive, or the general momentum of a situation.

Common Uses

  1. Physical force or speed: Describing how something moves or happens with power or speed.
  2. Impulse or sudden decision: Often used to express doing something on a sudden urge or without much thought.
  3. Momentum in situations: Used to describe the prevailing energy or trend, such as a team's winning streak or a growing movement.

Collocations and Patterns

  • 勢いよく (いきおいよく): vigorously, energetically — used to describe actions done with strong force or speed.
  • 勢いで + verb: doing something on impulse or without careful planning.
  • 勢いがある: having momentum or strong energy, often about groups or events.

Usage Notes

When using 勢い to describe impulse, it often implies a lack of careful thought, so it can carry a slightly negative nuance if the result is regretted. In contrast, when describing momentum or vigor, it usually has a positive or neutral tone.

Learners sometimes confuse 勢い with 力 (ちから, power) or エネルギー (energy). 勢い emphasizes the dynamic force or momentum behind an action rather than static strength.

Register

This word is common in both spoken and written Japanese and is neutral in formality, making it versatile for everyday conversation and media.

Example Sentences

かれはいきおいよくかいだんをかけあがった。

He ran up the stairs with great momentum.

いきおいでかったけど、あとでこうかいした。

I bought it on impulse, but regretted it later.

このチームはいきおいがあるから、ゆうしょうもゆめじゃない。

This team has momentum, so winning the championship is not just a dream.