The word 'wormy' is a straightforward English formation, combining the ancient noun 'worm' with the adjectival suffix '-y'. The core noun 'worm' originates from the Old English 'wyrm', which broadly referred to serpents, dragons, and creeping insects, a semantic range reflecting its Proto-Indo-European root wer-, meaning "to turn or bend." This root aptly captures the defining, sinuous motion of these creatures. Over time, the suffix '-y', a native English morpheme for forming descriptive adjectives, was appended to create 'wormy', literally meaning "full of or characterized by worms." The term's logic is transparent, moving from the literal description of infestation to a more figurative sense of being riddled or corrupted, much like wood bored through by worms.

Structure: worm (worm) + y (adjective suffix) - worm: From Old English 'wyrm', meaning a serpent, dragon, or creeping insect. Its ultimate Proto-Indo-European root is wer- (to turn, bend), describing the creature's sinuous movement. - y: A productive English suffix of Old English origin, used to form adjectives meaning "characterized by" or "full of."