IPA: /ˈkliːnliɪst/
KK: /ˈklɛnliɪst/
The highest degree of being free from dirt or impurities; the state of being the most tidy or pure.
She keeps her room the cleanliest of all her friends' rooms.
Comparative: cleaner
Superlative: cleanliest
Cleanliest → It is formed from "clean" (from Old English *clæne*, meaning free from dirt or impurities) and the superlative suffix "-liest" (meaning most). The word "cleanliest" means the most free from dirt or impurities.
Think of 'clean' meaning free from dirt, and when you add '-liest', it indicates the highest degree of cleanliness.
No commonly confused words.