The correct spelling of the word "un prolonged" is actually "unprolonged," without a space between the prefix "un-" and the root word "prolonged." The IPA phonetic transcription of this word is /ʌnprəˈlɒŋd/ with stress on the second syllable. The prefix "un-" means "not," and the root word "prolonged" means "extended in time." Therefore, "unprolonged" means "not extended in time" or "short-lived." It is important to pay attention to spelling and avoid misspellings to communicate effectively in written English.