Literally 'Wang the Fifth Old One' — the trope name comes from a 1937 film 《王老五》 about a poor old bachelor. The name then crystallized into a common label for never-married men.
usage
Often expanded to 钻石王老五 (zuànshí wánglǎowǔ, 'diamond bachelor') — a single, wealthy, eligible man, the Chinese counterpart of 'eligible bachelor'.
