This is the 11423rd most frequent Korean word.
깨지면서
"While breaking" or "as it breaks."
Here, '깨지면서' describes the simultaneous occurrence of falling and breaking of the glass cup.
유리잔이 떨어지면서 깨졌다.
The glass cup broke as it fell.
In this sentence, '깨지면서' is used metaphorically to describe the breaking of one's heart, leading to emotional consequences.
그의 마음이 깨지면서 깊은 슬픔에 잠기었다.
His heart broke, plunging him into deep sorrow.
'깨지면서' here metaphorically refers to the transition of the break of dawn signaling the start of a day.