There are numerous synonyms for the term "silly boy." Some alternatives include foolish lad, nonsensical lad, imprudent youngster, and childish bloke. Other terms that can be used to describe someone who is acting silly or childish include goofball, jester, clown, and buffoon. It is important to note that while these terms can be used playfully or endearingly among friends, they can also be harmful if used to belittle or undermine someone's intelligence or worth. It is important to use language and words that reflect kindness and respect towards others, especially when it comes to playful or teasing language.