This is the 9650th most frequent Japanese word.
膨れ
"膨れ" means "swelling" or "a puffed-up state."
The word "膨れ" is used to describe the swelling or increase of emotional intensity.
彼の怒りが膨れ上がった。
His anger swelled up.
Here, "膨れる" refers to the physical expansion of a balloon due to inflating.
風船が膨れるまで空気を入れてください。
Please pump air until the balloon swells.
In this case, "膨れて" is used to describe the puffing and expansion of bread during baking.