E. De Felice explains that this surname derives from an affectionate name: tenerello (in Neapolitan tenneriello), an affectionate diminutive of tenero (in Neapolitan tiénnero), meaning "full of tenderness, delicate". Its origin corresponds to the continental south of Italy.

E. Rossoni proposes that these forms would derive, directly or through hypocoristics, from the medieval name Tenerus. For Tenerelli in particular, he notes two independent stems of origin (ceppi): one in the Bari area and its surroundings, and another in the Catania area. The form Tenerello, very rare, seems typical of Sicily. Tenero is clearly concentrated in the Verona area, especially in Vigasio. Tennerello is specific to Caserta, while Tenneriello is located in Naples, Maddaloni and Prata di Principato Ultra.