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to congeal; to gelatinize; to jellify; to jell; to gell; to freeze
冷蔵庫に入れたスープが朝にはこごっていた。
The soup I put in the refrigerator had congealed by morning.
寒さで水たまりの表面がこごり始めた。
The surface of the puddle started to freeze in the cold.
煮こごりは魚の煮汁がこごったものである。
Nikogori is made from fish broth that has congealed.