The spelling of the word "was tail" is dictated by its phonetic pronunciation, which is /wɒz teɪl/. The first syllable is pronounced with the same vowel sound as "hot" or "not," while the second syllable is pronounced with the same vowel as "cake" or "fake." The "z" sound in "was" is pronounced like a voiced "s," while the "t" in "tail" is pronounced with a puff of air at the end, making it sound like "t-uh." Overall, the spelling accurately represents how the word sounds when spoken aloud.