Refers to the state of being newly married or to newlyweds; used in phrases like 'honeymoon' and 'newlyweds'.
新婚旅行でハワイに行く予定です。
We're planning to go to Hawaii for our honeymoon.
新婚の二人は幸せそうだった。
The newlyweds looked happy.
彼は新婚で忙しく、家にいる時間が少ない。
He's busy as a newlywed and spends little time at home.