The correct spelling of the word "antiatom" is /ˌæntiˈætəm/. The word is composed of the prefix "anti-" which means "against" and "atom" which refers to the smallest unit of matter. The pronunciation of the word is characterized by the short "a" sound in both syllables, followed by the stressed syllable, pronounced with an "uh" sound. The spelling follows the standard rules of English phonetics, with each letter representing a distinct sound.