汚い

1. Origins, structure, and basic meaning

• Structure: In 汚い (きたない), dirty 汚 plus adjectival い forms the adjective dirty.
• Basic usage: 汚い predicates or modifies something as dirty, while 汚く is the adverbial form before a following predicate.

2. Common pitfalls and similar expressions

• Dictionary and く forms
  • The target can distinguish physical dirt from a figurative judgment of underhanded behavior.