The word "peropus" is a non-existent English term. However, by using the International Phonetic Alphabet (IPA), we can breakdown its spelling. "p" is pronounced as /p/, "e" as /ɛ/, "r" as /r/, "o" as /ɑ/, "p" as /p/ and "us" as /ʌs/. This is the phonetic transcription of how the word sounds if it were an actual word. Proper spelling is important in communication, as it avoids any confusion and misunderstandings.
A monster with defective feet.
A practical medical dictionary. By Stedman, Thomas Lathrop. Published 1920.