From Japanese 山 (yama) meaning “mountain” and 口 (kuchi) meaning “mouth, entrance”. Olympic figure-skating champion Kristi Yamaguchi (1971-) bears this name.
From Greek ξύλον (xylon) meaning “wood, timber” and ἀνδρός (andros) meaning “man”. This surname was a Greek translation of German surnames of the same meaning.
From Chinese 许 (xǔ) referring to the minor state of Xu, which existed to the 4th century BC in what is now Henan province. The character 许 means “allow, permit”.
From Chinese 徐 (xú) referring to the ancient state of Xu, which existed to the 6th century BC in what is now Jiangsu and Anhui. The character 徐 means “slowly, calmly”.