〜ようものなら
Formation
Meaning
Expresses that if a certain action were to be taken, a serious or undesirable outcome would inevitably follow. Often used to emphasize a warning or a high risk.
Note
A formal and literary expression. It describes a hypothetical 'if' that leads to a very serious, troublesome, or undesired consequence. Often used when the speaker wants to emphasize a risk or threat.
Examples
油断しようものなら、大変なことになる。
If you were to let your guard down, something serious would happen.
一度失敗しようものなら、二度とチャンスは来ないだろう。
If one were to fail even once, another chance probably wouldn't come again.
妻に嘘を言おうものなら、すぐに見破られてしまう。
If I were to tell a lie to my wife, it would be seen through immediately.
遅刻しようものなら、部長にひどく怒られる。
If I were to be late, I would be severely scolded by the department manager.
不審な動きをしようものなら、すぐに警察に捕まるだろう。
If one were to make a suspicious move, they would be immediately caught by the police.
宿題を忘れようものなら、先生に厳しく注意される。
If one were to forget their homework, they would be strictly cautioned by the teacher.