This is the 1005th most frequent Korean word.
병원
Hospital.
In this sentence, '병원' refers to the physical healthcare facility that the speaker visited.
나는 병원에 갔다.
I went to the hospital.
In this context, '병원' is used to describe the institution where the mom is staying for medical treatment.
엄마가 병원에 입원 중이세요.
My mom is currently admitted to the hospital.
Here, '병원' indicates the location, emphasizing that the meeting with the doctor took place in the hospital.