Related Clues:

• Sings with closed mouth
• Crowd sounds
• Nature calls?
• Close-mouthed singing
• Guffaws
• Signs of kitty's contentment
• Some jungle sounds
• Sings along without words
• Comedy club reactions
• Pride sounds
• Laughs heartily
• Bellows, lion-style
• Is abuzz
• Acts contentedly
• Big laughs