Idiocy (noun)

1. The state of being mentally deficient or having a very low level of intelligence.
2. Acts or statements that are foolish or ridiculous.

Origin:

The word "idiocy" is derived from the greek word "idiotes" meaning a private person or someone who is not involved in public affairs. it refers to the state of being mentally deficient or having a very low level of intelligence.

Examples:

1. His idiocy was evident in the way he couldn't even perform basic math calculations.
2. The idiocy of the idea of building a wall to keep out immigrants was apparent to everyone.
3. He was fired for his idiocy in handling a client's account.
4. The idiocy of the political campaign was a source of amusement for many.
5. Her idiocy was on full display as she tried to argue with the teacher.