Latchkey child
n. 挂钥匙儿童
📖 牛津释义
latchkey child
(becoming dated 渐旧) child who has to let himself into his house or flat and look after himself, esp after returning from school, because both parents are out at work 挂钥匙的儿童（尤指因父母外出工作, 故放学回家需自行进屋的）.
🧩 词语组成解析
latchkey
[['lætʃki:]]
n. 弹簧锁钥匙
child
[tʃaɪld]
n. 小孩，孩子;幼稚的人;产物;弟子;
🗣️ 情景例句
By the way,
顺便问一声，
What's the population of China?
中国有多少人口？
No, by air.
不，坐飞机去。