firstborn

 Longman Dictionary of Contemporary English 5++朗文当代英语 5++LDOCE 5++朗文 5++first·born /ˈfɜːstbɔːn $ ˈfɜːrstbɔːrn/ noun [singular]  CHILDyour first child 头胎的孩子 —firstborn adjective her firstborn son 她的长子

Examples from the Corpus

firstborn• Often, the firstborn are favoured from the moment of birth.• They were expecting a son, brother to 2-year-old Hannah, their firstborn.

first·born nounChineseSyllable  

first child your Corpus

firstborn
first‧born /ˈfɜːstbɔːn $ ˈfɜːrstbɔːrn/ noun [singular]
your first child
—firstborn adjective:
    her firstborn son

first·bornBrE /ˈfɜːstbɔːn/ 🔊NAmE /ˈfɜːrstbɔːrn/ 🔊 noun (old-fashioned) a person's first child 头胎；长子；长女▸ first·born adjective [only before noun] ◆their firstborn son他们的长子