贻害无穷
yí​hài​wú​qióng

to have endless disastrous consequences

Senses

贻害无穷/ 貽害無窮 yí​hài​wú​qióng to have endless disastrous consequences

to leave behind a trail of trouble that never ends; to have long-lasting and severe negative consequences; also written as 贻患无穷 yí​huàn​wú​qióng

References

variant 贻害无穷/貽害無窮 → 贻患无穷/貽患無窮