‘昆玉’ is a highly respectful, literary term used to refer to someone else’s son. It is not used for one’s own child—only when addressing or speaking about another person’s son in formal or polite contexts, such as letters, speeches, or ceremonial occasions. The character ‘昆’ originally means ‘elder brother’ but here evokes kinship and virtue; ‘玉’ (jade) symbolizes purity, excellence, and nobility—so together, ‘昆玉’ metaphorically presents the son as a precious, virtuous jewel of the family.

This term belongs to classical Chinese honorific vocabulary and remains in use today mainly in written communication or elevated spoken registers—such as congratulatory messages, wedding invitations, or formal introductions. It is never used casually or among peers. Unlike common terms like ‘令郎’ (lìng láng), ‘昆玉’ carries an even more refined, slightly archaic tone and implies deep admiration for both the son’s character and the parents’ upbringing.