This is the 5909th most frequent Japanese word.
むせ返る
To choke or be overwhelmed (often by a strong smell, heat, or emotion).
In this sentence, "むせ返る" is used to describe how the air was overwhelming with the strong scent of flowers, creating a sensation of being overly immersed in the fragrance.
教室は花の香りでむせ返っていた。
The classroom was choking with the scent of flowers.
Here, "むせ返る" illustrates the physical reaction of choking or coughing because of the intense spices in the food.
スパイスの効いた料理を食べた彼はむせ返った。
He choked on the heavily spiced dish he ate.
In this example, "むせ返る" conveys the idea of oppressive or overwhelming heat, akin to a suffocating sensation when exposed to such conditions.