כנראה שמקור השם לקוח מהשמות הנפוצים של הממלכה האוסטרו-הונגרית השם גרובר נפוץ מאד באוסטריה
DIctionary of Surnames: Gruber: Someone who dwells near a mine, ditch or quarry. Someone who lives in the lower ground. Name common in the province of Tyrol (Tirol), Austria in 1369
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Balázs Déri's opnion:
Some of Gruber families though may descend from one of the persons called in the Byble as Er-Ge-Be-Rawa whose name applied to german sense made finally Ge-Rawa-Be-Er that is Gruber.
Jews and christians read this name Ibri or something like that in that babylónian language.
See ,Permyakov,Georg,Görög,Grüner !