Peruggini is a graphic variant of the surname Perugini, characteristic of the Naples area and, in general, of central-southern Italy. The doubling of the consonant g responds to phonetic phenomena proper to the southern dialects, where consonant gemination is habitual and is reflected in the written spelling. It keeps the same etymology of the Perusia group: it derives from the medieval name Perusinus, a hypocoristic of Perusius (Perugia), used as a demonym applied to those native to the city of Perugia, in Umbria.

Consonant gemination is a linguistic phenomenon in which a consonant is pronounced lengthened or reinforced, as if it were double. The term comes from the Latin geminus (twin). In Italian it is very important because it distinguishes words: caro (dear) versus carro (cart), pala (shovel) versus palla (ball), pena (sorrow) versus penna (pen). The double consonant is not merely a spelling convention: it is actually heard in the pronunciation, with a more prolonged articulatory closure.

The distribution of the surname is concentrated in southern Italy, especially in the Naples area. It is rarely documented as an autonomous entry in the classic onomastic repertoires.