The authors agree that this surname derives from a nickname related to the characteristic of being left-handed. E. De Felice defines it as coming from the Sardinian manu manka, "left hand", and by extension "left-handed". E. Rossoni notes that it should derive from dialect nicknames linked to that same characteristic, with the expression sa manu 'e manca, "the left hand", connected with the Latin manca. V. Blunda supplies a Sicilian perspective: he identifies the dialect term mànca with the meaning "left, left hand", a trait which in periods of clear right-handed dominance was distinctive enough to give rise to a nickname and then to become a surname.

As regards geographical distribution, Rossoni specifies that the surname is clearly proper to Sardinia, although he also records an area of presence in the Salento —that is, the southernmost zone of the region of Puglia, in southern Italy—, and documents its antiquity in Sardinia through medieval references such as the Condaghe di Santa Maria di Bonarcado, the Condaghe di San Nicola di Trullas and the Peace of Eleonora of 1388. De Felice also notes Sardinia as a region of high frequency. Blunda, by contrast, presents it as a Sicilian surname, which suggests that the surname has independent origins in different regions of Italy.