This is the 14th most frequent Korean word.
더
"더" means "more" in English.
The word '더' is used here to mean 'more' to indicate a greater amount of books that the speaker wants to read.
나는 더 많은 책을 읽고 싶어요.
I want to read more books.
Here, '더' is used to mean 'further' or 'longer,' extending the duration of an action, which in this case is waiting.
조금 더 기다려 주세요.
Please wait a little longer.
In this sentence, '더' means 'more' in the comparative sense to indicate an improvement in the weather compared to yesterday.