The term 'young fella' is a colloquial way of referring to a young man. It can be broken down into four different words: LAD (3 letters), SONNY (5 letters), KIDDO (5 letters), and BOY (3 letters). LAD is a British term for a young man, while SONNY is an affectionate term for a young BOY. KIDDO is a slang term for a child, and BOY is a general term for a male child. All of these terms are used to refer to a young man in a friendly or endearing way.