noun
future trouble; future problems
Refers to negative consequences or difficulties that may arise later as a result of current actions or decisions. Often used in cautionary contexts.
今のうちに問題を解決しておかないと、後患を残すことになる。
If we don't solve the problem now, it will leave future trouble.
彼は後患を恐れて、その計画に反対した。
He opposed the plan for fear of future problems.