/ˈeldɪst ||; ˈɛldɪst/adj noun[C] (the) oldest (of three or more members of a family) （三个或以上的家庭成员中）年纪最大的: Their eldest child is a boy. 他们的老大是个男孩。John's got 4 boys. The eldest has just gone to university. 约翰有4个儿子，大儿子刚进大学。