The term 'sound of disapproval' can refer to a variety of noises made to express disapproval or dissatisfaction. The crossword solutions for this term include 'HISS' (4 letters), 'tsk' (3 letters), 'CATCALL' (7 letters), 'HISSING' (7 letters), 'RASPBERRY' (9 letters), 'TUT' (3 letters), 'BOO' (3 letters), 'HOOT' (4 letters), and 'bronxcheer' (10 letters). A HISS is a sharp, sibilant sound made by forcing air through a small opening between the tongue and the roof of the mouth. A tsk is a sound made with the tongue and teeth to express disapproval or disappointment. A CATCALL is a loud, coarse whistle or shout made to express disapproval or contempt. HISSING is the act of making a HISSING sound. A RASPBERRY is a sound made with the lips to express contempt or disapproval. A TUT is a sound made with the tongue to express disapproval or disappointment. A BOO is a loud, harsh cry made to express disapproval or contempt. A HOOT is a loud, prolonged sound made to express disapproval or derision. A bronxcheer is a loud, raucous cheer made to express disapproval or derision.