Arthur, William (1857) An Etymological Dictionary of Family and Christian Names. New York: Sheldon, Blakeman. Public Domain.
MELLIS
As described in historical dictionaries
An Etymological Dictionary of Family and Christian Names (1857)
Sweet, from Mel, honey, or Gaelic, milis, sweet, or from Milidh, a soldier.
Surname type: Location or geographical feature
Origin: Celtic
Region of origin: British Isles
Country of origin: Scotland
Religion of origin: Christian
Language of origin: Gaelic