(used with a plural verb)markings, as initials, slogans, or drawings, written, spray-painted, or sketched on a sidewalk, wall of a building or public restroom, or the like: These graffiti are evidence of the neighborhood's decline.
(used with a singular verb)such markings as a whole or as constituting a particular group: Not much graffiti appears around here these days.
Origin of graffiti
1850–55; < Italian, plural of graffito incised inscription or design, derivative with -ito-ite2 of graffiare to scratch, perhaps influenced by presumed Latin*graphīre to write; both probably derivative of Latingraphium stylus < Greekgrapheîon; cf. graphic, grapho-, graft1
Related formsgraf·fi·tist, noun
In formal speech and writing graffiti takes a plural verb. In less formal contexts it is sometimes considered a mass noun and is used with a singular verb. The singular graffito is found mostly in archaeological and other technical writing.
1851, for ancient wall inscriptions found in the ruins of Pompeii, from Italian graffiti, plural of graffito "a scribbling," a diminutive formation from graffio "a scratch or scribble," from graffiare "to scribble," ultimately from Greek graphein "to scratch, draw, write" (see -graphy). Sense extended 1877 to recently made crude drawings and scribbling.