Meaning of the word "smart alec" in English

What does "smart alec" mean in English? Explore the meaning, pronunciation, and specific usage of this word with Lingoland.

smart alec

US /ˌsmɑːrt ˈæl.ɪk/
UK /ˌsmɑːt ˈæl.ɪk/

Noun

a person who is irritating because they behave as if they know everything

Example:
Don't be such a smart alec, just answer the question directly.
He always has a sarcastic comment, a real smart alec.