The phrase "hadst an urge for" is an outdated way of saying "you had an urge for." The word "hadst" is a contraction of "had" and "thou," a second person singular pronoun in early modern English. Its IPA phonetic transcription is /hædst/. The use of "an" before "urge" is also archaic and was common in earlier English. It is pronounced /æn/. Despite its historical significance, "hadst an urge for" is not commonly used in modern English.