having a very severe effect, or being extremely limiting

The most stringent laws in the world are useless unless there is the will to enforce them. 除非能够坚持严格执法，否则即使是世界上最严苛的法律也毫无用处。

We need to introduce more stringent security measures such as identity cards. 我们需要采取更为严格的安全措施，例如发放身份证。

Stringent safety regulations were introduced after the accident. 事故之后制定了严格的安全规范。

involving not enough money being available for borrowing as a result of firm controls on the amount of money in an economy

Already low living standards have been worsened by stringent economic reforms. 收紧银根的经济改革令本已很低的生活水平雪上加霜。