The word "derodidymus" is a medical term that refers to a type of muscle in the human body. Its correct spelling is "derodidymus," which is pronounced /dee-roh-dahy-duh-muhs/ in IPA phonetic transcription. The first syllable "dee" is stressed, followed by "roh" and "dahy." The second-to-last syllable "duh" is also stressed, and the final syllable "muhs" is pronounced with a soft "s" sound. The spelling of the word follows the usual rules of English pronunciation, with each syllable having a vowel sound.
A twin monster as to the head and neck, but with a single body.
A practical medical dictionary. By Stedman, Thomas Lathrop. Published 1920.