This is the 1407th most frequent Korean word.
오랫동안
For a long time.
In this sentence, "오랫동안" is used to describe the duration of the action "기다렸다" (waited).
그는 오랫동안 기다렸습니다.
He waited for a long time.
Here, "오랫동안" highlights the extended period of not meeting with "만나지 못하다" (not meet).
우리는 서로를 오랫동안 만나지 못했어요.
We haven't met each other for a long time.
"오랫동안" here denotes the extended period over which the dream was cherished or nurtured.