The term 'contented sounds' refers to the noises made by animals and humans that express contentment. This term can be broken down into four crossword solutions: PURRS (5 letters), coos (4 letters), aahs (4 letters), and ahs (3 letters). PURRS are the low, vibrating sounds made by cats and other felines when they are content. Coos are the soft, murmuring sounds made by birds, especially doves, when they are content. Aahs are the sounds made by humans when they are expressing contentment or pleasure. Lastly, ahs are the sounds made by humans when they express surprise or admiration.