Chinese: Mandarin form of the surname 雷 meaning ‘thunder’ in Chinese: (i) from the second element of Fang Lei (方雷) the name of an ancient state prior to the Xia dynasty (2070–1600 BC). The state is said to have been named for Fang Lei Shi son of the legendary king Yu Wang (traditional dates: 4561–4494 BC) associated with a fief called Fangshan (perhaps in present-day Yuzhou or Songshan in Henan province). Some of the people from the state acquired 雷 as their surname while others acquired 方 (Fang) as their surname. (ii) said to be traced back to Lei Gong (雷公) a famous doctor during the reign of the legendary Huang Di the Yellow Emperor (c. 27th century BC). Chinese: Cantonese form of the surnames 李 and 利 see Li 1 and Chinese: variant Romanization of the surname 呂 see Lu 6. Dutch: nickname for a lazy person from Middle Dutch lei ‘lazy’.
Source: Dictionary of American Family Names 2nd edition, 2022