uncleanliest
/ʌnˈklɛnliɪst/
adjective
- Most dirty or impure; the superlative form of 'uncleanly' meaning having the highest degree of filth or lack of cleanliness.
- The health inspector said this was the uncleanliest kitchen he had ever seen in a restaurant.
- After the flood, the water left the uncleanliest residue on every surface.
- Of all the rooms in the old house, the basement was the uncleanliest, covered in dust and cobwebs.