Sketchy comes from sketch (from Dutch schets, from Italian schizzo, ultimately from Latin schedium 'extempore poem', from Greek skhedios 'sudden') plus the suffix -y. The historical chain includes Ancient Greek skhedios. Older glosses in the chain include "extempore poem" and "sudden", which help explain the semantic range of the modern word. Morphologically, sketchy is best read as suffixal formation and borrowing, yielding an English adjective shaped by both form history and later usage. In current English it functions as an adjective, with the sense "incomplete or rough; informally, dubious or untrustworthy". English derivatives include sketchily and sketchiness; related forms include sketch and sketcher. The result is an English adjective whose etymology preserves the older forms while supporting the word's specialized modern meaning.