The term 'chuckling sound' can be described by two crossword solutions: HEH (3 letters) and HEEHEE (6 letters). HEH is an expression of laughter, usually used to indicate amusement or surprise. It is a short, lighthearted sound that is often used in informal conversations. HEEHEE is a more exaggerated version of the same sound, usually used to express joy or excitement. Both sounds are commonly used to express amusement or joy in response to something humorous.