1. One who is stupid or foolish. Geez, he keeps pulling on a door that's clearly marked "push"—what a dingleberry.
2. A small piece of feces stuck to the hair on the buttocks. Aw man, it looks like the dog's got a dingleberry.
dingleberry
1. n. a blob of fecal matter clinging to the hairs around the anus. (Usually objectionable.) Is there no permanent cure for the heartbreak of dingleberries?
2. n. a stupid-acting person of either sex. You are such a dumb dingleberry! Wise up!