【Slatternly】 , 【dowdy】 , 【frowzy】 , 【blowsy】 can all mean deficient in neatness, freshness, or smartness, especially in dress or appearance.
【Slatternly】 stresses notions of slovenliness, unkemptness, and sordidness.
【Dowdy】 is likely to imply a complete lack of taste typically marked by a blend of something untidy, drab, or tawdry.
【Frowzy】 suggests a lazy lack of neatness, order, and cleanliness, but 【frowzy】 also may apply to a natural and not unwholesome disorder or it may suggest drab misery and squalor as an inevitable result of circumstances.
【Blowsy】 implies dishevelment or disorder to which is often added a notion of crudity or coarseness or grossness.