The kanji 汚 primarily conveys the meaning of "dirty," "filthy," or "to pollute." It refers to something that is unclean, contaminated, or morally tainted. This can apply to physical objects, environments, or even abstract concepts like reputations.

・On-yomi (音読み): オ ・Kun-yomi (訓読み): けが-す、けが-れる、よご-す、よご-れる

⚫︎汚い部屋 Translation: A dirty room ⚫︎汚染 Translation: Pollution ⚫︎汚職事件 Translation: Corruption case

The kanji 汚 is a phono-semantic compound (形声文字). The left side is the water radical 氵 (さんずい), which represents water. The right side is the phonetic component 亏 (き), which contributes to the sound and suggests a relationship with the meaning. Therefore, the water radical combines with a phonetic component suggesting "loss" or "damage" to create the concept of dirty water or contamination.