to stand too long;
вода застоялася — the water is stagnant (stale, corrupt, foul, not fresh);кінь застоявся — the horse is restive.
Дієприслівникова форма: застоявшись
Деепричастная форма: застоявшись
"Honor is not the exclusive property of any political party." Herbert Hoover
"Hitch your wagon to a star." Ralph Waldo Emerson
"If fear is cultivated it will become stronger, if faith is cultivated it will achieve mastery." John Paul Jones
"Ambition is but avarice on stilts, and masked." Walter Savage Landor