pinhead

noun

1. the head of a pin.
2. something very small or insignificant.
3. Slang. a stupid person; nitwit.

noun

1. the head of a pin
2. something very small
3. informal a stupid or contemptible person

n.also pin-head, “head of a pin,” 1660s, from pin (n.) + head (n.). Meaning “person of small intelligence” is from 1896.