blazer
/ˈbleɪzə(r)/noun
1- a coloured summer jacket worn by schoolchildren or sports players as part of a uniform（中小学生、运动员夏季穿的, 作为制服一部分的）彩色夹克衫。
1.1
- a plain jacket, typically dark blue, not forming part of a suit but considered appropriate for formal wear（通常为深蓝色、不与裤子配套但被认为可在正式场合穿着的）便上装。
词源
late 19th cent.: from BLAZE1 + -ER1 . The original general sense was 'a thing that blazes or shines' （mid 17th cent.）, giving rise to the term for a brightly coloured sporting jacket.