Lower, Mark A (1860) Patronymica Britannica: a dictionary of the family names of the United Kingdom. London: J.R. Smith. Public Domain.
DENNIS
As described in historical dictionaries
Patronymica Britannica (1860)
DENNIS. DENIS. A baptismal name : the patron saint of France. Sometimes, however, as Ferguson observes, it may be from the A.-Sax. Denisca, Danish, and this is confirmed by the Le Deneys of the H.R.
Surname type: From given name or forename
Origin: English
Region of origin: British Isles
Country of origin: England
Religion of origin: Christian
Language of origin: English