second child
Refers to the second-born child in a family. Often used in formal or statistical contexts.
He was born as the second child.
The due date for the second child is next month.
Refers specifically to the eldest son, whereas 第二子 is gender-neutral and simply means second child.
Standard kanji spelling.
Variant using Arabic numeral 2 instead of 二.
Compound of 第 (ordinal prefix) + 二 (two) + 子 (child).