Lower, Mark A (1860) Patronymica Britannica: a dictionary of the family names of the United Kingdom. London: J.R. Smith. Public Domain.
LANGDON
As described in historical dictionaries
Patronymica Britannica (1860)
LANGDON. Parishes in Kent, Essex, &c. The Langdons of Cornwall derive from Langdon in the parish of Jacolstow, their ancient patrimony. C. S. Gilbert's Cornwall.
Surname type: Location or geographical feature
Origin: English
Region of origin: British Isles
Country of origin: England
Religion of origin: Christian
Language of origin: English