IPA: /ɪˈmæk.jʊ.lət/
KK: /ɪˈmæk.jə.lɪt/
Perfectly clean and free from any marks, stains, or errors.
The house was immaculate after the cleaning service finished their work.
Comparative: more immaculate
Superlative: most immaculate
Immaculate is formed from "in-" (meaning not) and "maculatus" (from Latin, meaning spotted or stained). The word describes something that is not spotted or stained, hence pure or clean.
Think of something that is 'not' ('in-') 'spotted' or 'stained' ('maculatus') — that's why immaculate means pure or clean.