From Longman Dictionary of Contemporary Englishdirtydirt‧y1 /ˈdɜːti $ ˈdɜːr-/ ●●● S2 W3 adjective (comparative dirtier, superlative dirtiest) 1 
not cleanDIRTY covered in or marked by an unwanted substance OPP clean a stack of dirty dishes in the sink How did you get so dirty?dirty clothes/washing/laundry She circled the bedroom, picking up dirty clothes.2 sexSYSEX/HAVE SEX WITH relating to sex, in a way that is considered immoral or unpleasant kids telling dirty jokes a dirty magazine She looked at me as if I had said a dirty word.have a dirty mind British English (=think about sex a lot)dirty weekend British English (=a weekend when a man and woman who are not married to each other go away to have sex)3 bad/immoralBAD used to emphasize that you think someone or something is bad, dishonest, or immoral You’re a dirty liar! a dirty fighter you and your dirty little dealsdo the dirty on somebody British English (=treat someone in a way that is unfair or dishonest) What a dirty trick!4 → something is a dirty word5 → give somebody a dirty look6 → dirty trick7 → wash your dirty linen/laundry8 → do somebody’s dirty work9 → it’s a dirty job, but someone has to do it10 drugsMDD American English informal containing or possessing illegal drugs11 → dirty bomb12 sport a dirty sports event is one in which people competing in the event have illegally used drugs to improve their performance Many people think that the race has been a dirty event for years.13 environment producing pollution or carbon dioxide dirty forms of energy —dirtily adverbTHESAURUSdirty not cleanHis clothes were untidy and he had dirty hands.filthy very dirtyEach year filthy water causes millions of cases of illness.muddy covered with mudIt had been raining hard and the path was muddy.dusty covered with dustthe dusty shelves in the atticgreasy covered with oil or greaseGreasy food is bad for your health.grubby (also mucky British English) informal fairly dirty and needing to be cleaned or washedHe was wearing a grubby white T-shirt.mucky fingersgrimy covered with thick dirt or dirt that has been there a long timeI couldn’t see much out of the grimy windows of the train.dingy /ˈdɪndʒi/ looking dark, dirty, and unpleasant. Used about rooms, houses, and buildingsWe worked in a dingy little office behind the station.polluted used about land, water, or air that has been made dirty85% of city dwellers breathe heavily polluted air.contaminated made dirty by a dangerous substance or bacteriaThe virus is mainly spread through contaminated food.squalid /ˈskwɒləd $ ˈskwɑː-/ formal extremely dirty and unpleasant. Used about the place or conditions in which someone livesPeople are living in squalid conditions, with little water and no sanitation.unhygienic /ʌnhaɪˈdʒiːnɪk◂ $ -ˈdʒe-, -ˈdʒiː-/ formal used about dirty conditions that are likely to cause disease, especially conditions in kitchens, restaurants, and hospitalsThe food was prepared under unhygienic conditions.unsanitary (also insanitary British English) formal used about dirty conditions that are likely to cause disease, especially because there is not a good system for getting rid of wastePeople’s health is being threatened by overcrowded and insanitary homes.They work for long hours in unsanitary conditions.soiled formal made dirty, especially by waste from your bodySoiled nappies should be changed as quickly as possible.
not cleanDIRTY covered in or marked by an unwanted substance OPP clean a stack of dirty dishes in the sink How did you get so dirty?dirty clothes/washing/laundry She circled the bedroom, picking up dirty clothes.2 sexSYSEX/HAVE SEX WITH relating to sex, in a way that is considered immoral or unpleasant kids telling dirty jokes a dirty magazine She looked at me as if I had said a dirty word.have a dirty mind British English (=think about sex a lot)dirty weekend British English (=a weekend when a man and woman who are not married to each other go away to have sex)3 bad/immoralBAD used to emphasize that you think someone or something is bad, dishonest, or immoral You’re a dirty liar! a dirty fighter you and your dirty little dealsdo the dirty on somebody British English (=treat someone in a way that is unfair or dishonest) What a dirty trick!4 → something is a dirty word5 → give somebody a dirty look6 → dirty trick7 → wash your dirty linen/laundry8 → do somebody’s dirty work9 → it’s a dirty job, but someone has to do it10 drugsMDD American English informal containing or possessing illegal drugs11 → dirty bomb12 sport a dirty sports event is one in which people competing in the event have illegally used drugs to improve their performance Many people think that the race has been a dirty event for years.13 environment producing pollution or carbon dioxide dirty forms of energy —dirtily adverbTHESAURUSdirty not cleanHis clothes were untidy and he had dirty hands.filthy very dirtyEach year filthy water causes millions of cases of illness.muddy covered with mudIt had been raining hard and the path was muddy.dusty covered with dustthe dusty shelves in the atticgreasy covered with oil or greaseGreasy food is bad for your health.grubby (also mucky British English) informal fairly dirty and needing to be cleaned or washedHe was wearing a grubby white T-shirt.mucky fingersgrimy covered with thick dirt or dirt that has been there a long timeI couldn’t see much out of the grimy windows of the train.dingy /ˈdɪndʒi/ looking dark, dirty, and unpleasant. Used about rooms, houses, and buildingsWe worked in a dingy little office behind the station.polluted used about land, water, or air that has been made dirty85% of city dwellers breathe heavily polluted air.contaminated made dirty by a dangerous substance or bacteriaThe virus is mainly spread through contaminated food.squalid /ˈskwɒləd $ ˈskwɑː-/ formal extremely dirty and unpleasant. Used about the place or conditions in which someone livesPeople are living in squalid conditions, with little water and no sanitation.unhygienic /ʌnhaɪˈdʒiːnɪk◂ $ -ˈdʒe-, -ˈdʒiː-/ formal used about dirty conditions that are likely to cause disease, especially conditions in kitchens, restaurants, and hospitalsThe food was prepared under unhygienic conditions.unsanitary (also insanitary British English) formal used about dirty conditions that are likely to cause disease, especially because there is not a good system for getting rid of wastePeople’s health is being threatened by overcrowded and insanitary homes.They work for long hours in unsanitary conditions.soiled formal made dirty, especially by waste from your bodySoiled nappies should be changed as quickly as possible. Examples from the Corpus
dirty• How did the floor get so dirty?• We were hot and dirty after working in the garden all afternoon.• He used to keep a collection of dirty books hidden under his bed.• Do you have any dirty clothes you need me to wash?• The air in El Paso is arguably the dirtiest in Texas, violating federal standards for ozone, carbon monoxide and particulates.• Take off those dirty jeans.• Having to lay employees off is a dirty job.• They just sit around telling dirty jokes - it's very boring.• I didn't anticipate spending days mucking out some of the dirtiest piggeries I had ever seen.• The government led a dirty war against its own citizens.• Look how dirty your hands are!have a dirty mind• You psychologists all have dirty minds.dirtydirty2 adverb informal 1 → play dirty2 → talk dirty3 → dirty great/dirty bigdirtydirty3 verb (dirtied, dirtying, dirties) [intransitive, transitive] 1 DIRTYto make something dirty2 to make someone feel or seem bad, dishonest, or immoral The army’s actions dirtied its reputation.3 → dirty your hands→ See Verb tableExamples from the Corpus
dirty• He opened a book with his thumbnail, as if afraid of dirtying his fingers.• As he stood on the pavement, muddy water splashed up and dirtied his trousers.• The army, long seen as standing above the fray, dirtied its reputation in Kashmir earlier this year.• There were cigarette butts and dirtied napkins everywhere.• You can borrow my gloves, but please try not to dirty them.From Longman Business Dictionarydirtydirt‧y /ˈdɜːtiˈdɜːr-/ adjective unfair or dishonesta dirty political campaignrevelations about dirty dealing in the Treasury bond marketHe accused the government of dirty tricks against the Republicans. 