The phrase "hast part in" is a common but outdated way of expressing involvement in something. It is derived from Middle English and is spelled phonetically as /hæst pɑrt ɪn/. The word "hast" is the second person singular form of the verb "have", while "part" is the noun meaning "portion" or "share". The "in" at the end denotes the place of involvement. Although not commonly used today, understanding the phonetic transcription can help one decipher the meaning of the phrase in older literature.