A rare linguistic term referring to humble language, synonymous with the more common 謙譲語 (けんじょうご). Used in discussions of Japanese honorifics.
See also: 謙譲語
In Japanese honorifics, there is also a classification that includes respectful language, humble language, and 謙遜語.
Compound of 謙遜 (けんそん, 'humility') and 語 (ご, 'language'). The exact historical derivation is uncertain, but it follows the pattern of other honorific language terms.