That bar is the sleaziest in town, with peeling wallpaper and wobbly furniture.

sleaziest 是形容词 sleazy 的最高级形式。sleazy 意思是"肮脏破旧的、低劣的"，常用来形容环境或场所破败不堪的状态。sleaziest 表示"最破旧的"，强调程度达到极点。