The spelling of "was down the mouth" is based on the IPA phonetic transcription. The word "was" is pronounced as /wʌz/, with the "a" pronounced like the "u" in "umbrella". The phrase "down the mouth" is pronounced as /daʊn ðə maʊθ/, with the "ou" pronounced like the "ow" in "cow" and the "th" pronounced as a voiced "th" sound. Together, the phrase means feeling sad or upset, and its spelling accurately reflects its pronunciation.