This is the 3294th most frequent Korean word.
기쁨을
"기쁨을" means "joy" or "happiness" in English (accusative form).
Here, '기쁨을 느꼈다' describes the feeling of joy experienced in the stated situation.
그녀는 친구들과 시간을 보내며 기쁨을 느꼈다.
She felt joy while spending time with her friends.
In this sentence, '기쁨을 주는' is used as an attribute to describe the gift that provides joy.
기쁨을 주는 선물을 받았어요.
I received a gift that brings joy.
Here, '기쁨을 이해하기' pertains to comprehending the joy that someone else is experiencing.