The term 'nervous giggle' can be described by two crossword solutions: 'TITTER' (6 letters) and 'TEHEE' (5 letters). A TITTER is a light, nervous laugh, usually in response to an awkward or embarrassing situation. TEHEE is a sound made when someone is amused or finds something funny. Both words are used to describe a nervous giggle, which is a short, high-pitched laugh that is often used to express embarrassment or awkwardness.