This is the 3842nd most frequent Korean word.
아이
Child.
Here, '아이' means 'child' and is used as the subject of the sentence, denoting a young human.
아이가 공원에서 놀고 있어.
The child is playing in the park.
In this sentence, '아이' is used metaphorically to imply innocence and purity.
나는 아이처럼 순수한 마음을 가지고 싶어.
I want to have a pure heart like a child.
The word '아이들' is the plural form of '아이', indicating a group of children.