1 to develop into an adult; to mature 长大成人；成熟: What do you want to be when you grow up?(= what job do you want to do later?) 你长大后想做什么？She grew up(= spent her childhood)in Spain. 她是在西班牙长大的。

2 (used about a feeling, etc) to develop or become strong （指感情等）形成，变得强烈: A close friendship has grown up between them. 他们建立起亲密的友谊。