Chinese: Mandarin form of the surname 單: (i) from the placename Shan (單) the name of a fief (located in Mengjin in present-day Henan province) granted to Zhen the youngest son of King Cheng of Zhou (reigned 1042–1021 BC). (ii) borne by the A Shan (阿單) Ke Shan (可單) and He Shan (紇單) families from the Xianbei ethnic group in northern China. They shortened their original surnames to 單 during the Northern Wei dynasty (386–534 AD). Chinese: Mandarin form of the surname 山 meaning ‘mountain’ in Chinese: (i) from Shan Shi (山師) (literally meaning ‘mountain officer’) the title of an official post in charge of mountains and forests during the Western Zhou dynasty (1046–771 BC). People adopted part of the title 山 as their surname. (ii) from Shu Shan Ran (叔山冉) an official in the state of Chu during the Spring and Autumn period (770–476 BC). Some of his descendants inherited 山 part of his name as their surname. (iii) borne by the Tu Nan (吐難) family from the Xianbei ethnic group in northern China who changed their original surname to 山 during the Northern Wei dynasty (386–534 AD). Indian (Gujarat): Vania name of unexplained etymology. English: unexplained.
Source: Dictionary of American Family Names 2nd edition, 2022