The spelling of the word "haddest a whack" is interesting and confusing to many. The word is pronounced /ˈhædəst ə wæk/ and is a Middle English phrase meaning "you hit" or "you struck." The spelling can be attributed to the archaic language used during that time, where double consonants were common. Additionally, it is believed that the suffix "-est" was added to verbs in the second person singular to form the past tense. The word "whack" remains the same in modern English but the conjugation has changed.