Pollex pepis refers to the anatomical term for a human's thumb muscle. The spelling of this word is derived from Latin, where "pollex" means thumb and "pepis" refers to the muscle that controls the thumb's movement. The correct pronunciation of this term would be pɒlɛks ˈpɛpɪs. The IPA phonetic transcription can help to understand the correct pronunciation of this term, which is essential to ensure clarity in medical communication. It is also helpful to understand the origin and meaning of medical words to better comprehend their usage.