1.
carelessness is one's greatest enemy, overconfidence is dangerous
A warning that letting one's guard down or becoming complacent can lead to failure.
油断大敵だから、気を引き締めよう。
Carelessness is the enemy, so let's stay focused.
試合は最後まで油断大敵だ。
In a match, you can't let your guard down until the end.
合格したと思っても油断大敵だよ。
Even if you think you passed, don't get overconfident.
A well-known 四字熟語 (four-character idiom) meaning "carelessness is one's greatest enemy."
COMPOSITION:
- 油断: carelessness, letting one's guard down
- 大敵: great enemy, formidable foe
USAGE:
- Used as a standalone warning: 油断大敵だ (Carelessness is dangerous!)
- Common in sports, exams, work, and safety contexts
- Often used to motivate continued effort even when things seem to be going well
- Frequently appears on posters and signs in workplaces
SIMILAR EXPRESSIONS:
- 油断するな: Don't let your guard down
- 気を抜くな: Don't lose focus
- 油断は禁物: Carelessness is forbidden
Equivalent English proverbs: "Don't count your chickens before they hatch," "Pride goes before a fall."