The correct spelling of the word is clouds /klaʊdz/. The first sound is a voiced velar stop, /k/, followed by the diphthong /laʊ/, which begins with an open front unrounded vowel /a/ and ends with a close back rounded vowel /ʊ/. The final sound is a voiced alveolar fricative /z/. The word is an irregular plural of cloud, which means a visible mass of condensed water vapor floating in the atmosphere.