Nestohedron is a rare word that is not commonly used in everyday conversation, but it appears in mathematical contexts. According to the International Phonetic Alphabet (IPA), the word is spelled /nɛstoʊhɛdrən/. The first syllable "nes" is pronounced as "nezz" with a short "e" sound. The second syllable "to" is pronounced as "toh" with a long "o" sound. The third syllable "he" is pronounced as "he" with a short "e" sound. The last syllable "dron" is pronounced as "drən" with the schwa sound.