The authors agree that the surname derives from the term rubinus, linked to the precious stone of the ruby. E. De Felice notes that the surname was formed from a name and nickname already documented in Venice at the end of the 13th century —under the forms Rubin or Rubinus—, with the sense of "dear, precious thing; beautiful as a ruby." F. Miranda specifies that the medieval name Rubinus comes from the Latin ruber ("red") and that the surname would have arisen as a nickname for people with reddish eyes or hair.

Both Miranda and G. P. Holmes gather hypotheses of Hebrew origin. Holmes points to the Hebrew ruben, with the meaning of "son of Providence." Miranda, for his part, mentions the Hebrew term ruba ("admirer" or "lover"), possibly adopted by Sephardic Jews later established in Italy, and also the hypothesis that Rubino could derive by aphaeresis from the medieval name Cherubino, originated in the Hebrew Kerubin, with the sense of "spirit, winged angel."

As to its geographic distribution, De Felice indicates that the surname is more frequent in southern Italy under the forms Rubino or Rubbino, while in the north the variant Rubini predominates; the forms Rubin and Rubinato are proper to the north-east of Italy, in the regions of Veneto, Friuli-Venezia Giulia and Trentino-Alto Adige. Miranda adds that it is especially widespread in Apulia, Sicily, Campania, Calabria and Basilicata, with a presence also in Piedmont, Lombardy, Lazio, Liguria and Tuscany.