cause for concern; source of unease
Refers to a factor, piece of information, or situation that creates anxiety or worry. Often used in news, business, or personal contexts.
景気の減速は投資家にとって不安材料だ。
The economic slowdown is a cause for concern for investors.
彼の健康状態が不安材料になっている。
His health condition has become a source of unease.