The authors differ on the origin of this surname. E. Rossoni considers it widespread in southern Italy and finds no solid hypothesis as to its provenance, although he points —on a purely theoretical level— to a possible derivation from the Lombard name Erlembald, or else to a modification and contraction of the name Guglielmo, by way of the forms Lelmo and Lembo.

V. Blunda proposes a Sicilian dialect origin: the surname would derive from the word lèmmu, which designates an earthenware basin or tub used for kneading bread or washing utensils. According to Blunda, the surname could have arisen from the trade of the potter who made those vessels, or from a nickname applied to the pedlar who sold them. G. P. Holmes agrees on the reference to the terracotta bowl as a Sicilian term, without adding further development.