The wiki has this about the Etymology;
Gryffindor could possibly be derived from griffin, which is a creature in mythology with the body of a lion and the head of an eagle.
In Old English and Old High German dor means gate or door.
In French "d'or" means "of gold," one of the Gryffindor House colours, though it can also come from the Greek word "dora" meaning "gift".
A combination can be assumed; "Golden Gift of the Lion".
"Griffe" (from the Latin "gryphus", which means "curved nose") is the French word for "claw", which could refer to the claw of the lion.
"Gryffindor" could very well be explained by heraldry: "Gryffin" would then stand for the griffin beast, and the "[d]or" would refer to the metal tincture "[d'] or" (Middle English for "[of] gold", derived from French; corresponds to yellow).
Gryffindor is also a pun on the golden gryffin, which is a lion that only has eagle wings, so it has the head and front paws of a lion, and has golden fur and feathers. The French for Gryffindor, "Griffondor", is a homophone for the actual beast, Griffon d'Or. Similarly, the Italian "Grifondoro" is a homophone of Grifon d'Oro. Coincidentally, Italy also has a high number of cities and towns which present a golden gryffin in their coat of arms. Examples of this are Agnone, Alessandria, Arzignano and Genoa
