noun
supplementary prize; bonus prize
A prize given in addition to the main prize, often in contests, competitions, or lotteries. Not the top award.
コンテストで優勝は逃したが、副賞として図書券をもらった。
I missed first place in the contest, but I received a book voucher as a supplementary prize.
この宝くじの副
The bonus prize for this lottery is a travel voucher.