Goofball (noun)

1. A silly, foolish, or ridiculous person.
2. A person who is behaving in a silly or foolish way.

Origin:

Early 20th century: of uncertain origin. the term may be related to the phrase "goofing off" which means to waste time.

Examples:

1. He was always the class goofball, playing pranks and making jokes.
2. She was a goofball, always making silly faces and telling jokes.
3. He thought he was being funny, but he was just acting like a goofball.
4. He was a goofball, but she loved him for his sense of humor.
5. The party was full of goofballs, making everyone laugh.