Where does “grullerello” come from?

grullerello (Italian) comes from Italian grullo, from Lombardic grollo, from Proto-West Germanic *grulljō — grudge.

Ancestry of “grullerello”, step by step

StepLanguageWordMeaning
1Italiangrullostupid, silly; fool, idiot
2Lombardicgrollorancor, anger
3Proto-West Germanic*grulljōgrudge
Every word from Proto-West Germanic *grulljō →Every word from Lombardic grollo →Every word from Italian grullo →