し
知

れ

る

Ichidan verb, intransitive verb

1. to become known, to come to light, to be discovered.
2. to be known, to be understood. Usu. in the negative.
3. to clearly not amount to much, to be insignificant.
4. to be evident, to be obvious, to go without saying. As 知れたこと.
5. to be very intense (of worry, hope, etc.), to be severe. As どんなに…か知れない, どれほど...か知れない, etc..