stepbrother
n. (繼母與其前夫或繼父與其前妻所生的)哥哥,弟弟
Someone's stepbrother is the son of their stepfather or stepmother.
1. a son of your stepparent by a former marriage
One of his stepbrothers is called Walter, the other one was called Herbie.
母親再婚後,他多了兩哥哥,叫瓦爾特和赫比.