stagnate

The water in the pond began to stagnate.

池の水がよどみ始めた。

Without new challenges, his career began to stagnate.

新しい挑戦がなければ、彼のキャリアは活気を失い始めた。

The dam stagnated the river's flow.

ダムが川の流れをよどませた。

The lack of innovation stagnated the company's growth.

革新の欠如が会社の成長を停滞させた。