Wiseacre (noun)

A person who pretends to be wise or clever, but is actually foolish or superficial.

Origin:

From the word "wise" meaning smart and "acre" meaning land. it is a wordplay on the phrase "wise acre".

Examples:

1. He was a wiseacre who thought he knew everything but actually knew nothing.
2. She was tired of listening to the wiseacre's empty boasts.
3. The wiseacre's attempts at humor were met with groans.
4. He was a wiseacre, always trying to one-up everyone with his knowledge.
5. The wiseacre's braggadocio made him hard to take seriously.