Pinhead (noun)

1. A tiny head on a pin.
2. A very small or insignificant person or thing.

Origin:

Pinhead comes from the middle english word "pinhede" meaning "small head of a pin".

Examples:

1. The pinhead was too small to see with the naked eye.
2. He felt like a pinhead being scolded by his boss.
3. The pinhead was so small that it took a magnifying glass to see it.
4. She was too busy to listen to the pinhead's complaints.
5. The pinhead size of the screw made it hard to handle.