Simple categories matching nasty:

• component,
• thing,
• pathogen,
• illness,
• stuff,
• beast,
• bug,
• disease,
• chemical,
• critter,
• creature,
• cause,
• animal,
• disorder,
• happening,
• contaminant,
• program,
• item,
• condition,
• virus,
• weather,
• pest,
• substance,
• sickness,
• std,
• content,
• infection,
• material,
• germ,
• insect,
• software,
• weapon,
• vice,
• compound,
• preservative,
• allergen,
• microbe,
• predator,
• parasite,
• bacteria,
• emotion,

Members with property nasty:

• virus,
• mercury,
• tornado,
• gelatin,
• kidney_infection,
• hospital_waste,
• yellow_teeth,
• worm,
• melting,
• trojan,
• anger,
• ant,
• strychnine,
• arsenic,
• ammonia,
• dog,
• roach,
• glycerin,
• methyl_chloride,
• oil,
• possum,
• fox,
• lead,
• spider,
• mild_acid,
• herpes,
• change,
• arab,
• cancer,
• portable_heater,
• mycoplasma,
• dysentery,
• dead_squirrel,
• rat,
• arson,
• alkali,
• cockroach_spider,
• acetylene,
• mite,
• pneumonia,
• dust,
• slider,
• bilharzia,
• shoes,
• rodent,
• pesticide,
• pus,
• cyanogen_bromide,
• despair,
• human_skin,
• toluene,
• tick,
• pollution,
• diphtheria,
• snow,
• smoke,
• damp_patch,
• osprey,
• parvo_germ,
• german_roach,
• cadmium,
• diabetes,
• klebsiella,
• snake,
• cheetah,
• silicon,
• phosphorus_bomb,
• nail-polish_remover,
• caulk,
• cholera,
• nighthawk,
• red_shell,
• death,
• desire,
• amoebic_dysentery,
• streptococcus,
• mycobacterium,
• typhoid,
• ghost,
• lye,
• sore_breast,
• bronchitis,
• intention,
• influenza,
• condom,
• chigger,
• vindictiveness,
• blood,
• harmful_parasite,
• ear_infection,
• staph,
• flea,
• giardiasis,
• innovation,
• rain,
• composition,
• insurance_cover,
• seat_adjuster,
• caustic_alkali,
• fecal_streptococcus,
• car_oil,
• constipation,
• mold,
• old_sock,
• hepatitis,
• beholder,
• glue,
• illness,
• tapeworm,
• fact,
• jealousy,
• sex,
• milkweed_bug,
• flashing,
• curve,
• trichloroethylene_tce,
• olive,
• spite,
• coating,
• hookworm,
• giardia,
• bacteria,
• carbon,
• mesothelioma,
• crack,
• listeria,
• venomous_snake,
• pneumococcus,
• dog_droppings,
• aubergine,
• phosphorus,
• centipede,
• ethnic_conflict,
• biting_bug,
• pipe_dope,
• alcohol,
• chromatic_aberration,
• sugar,
• genital_wart,
• perchlorate,
• poop,
• dirt,
• sls,
• venomous_frog,
• cockroach,
• dot,
• toxic_petrochemical,
• excessive_profanity,
• dioxin,
• stuff,
• paint,
• slug,
• flan,
• tb,
• blaster_worm,
• bird_droppings,
• sadness,
• colouring_agent,
• microscopic_cat,
• hatred,
• sealer,
• shigella,
• leptospirosis,
• microbe,
• graphic_depiction,
• organs,
• mouse,
• gangrene,
• competition,
• robbery,
• hurricane,
• crippling_injury,
• mink,
• dung,
• asbestos,
• quantum_fluctuation,
• staff,
• meningitis,
• yeast_infection,
• description,
• fighting,
• termite,
• rivalry,
• advertisement,
• steep_grade,
• wolf,
• blast_weapon,
• insecticide,
• car_crash,
• blast_armor,
• animal_testing,
• chloroform,
• water,
• banana,
• dog_dirt,
• savings_plan,
• spyware,
• envy,
• heart,
• common_cold,
• nitrate,
• toxic_metal,
• grease,
• people,
• scrapie,
• command,
• deer,
• turpentine,
• rickets,
• recording_sound,
• grasshopper,
• flu,
• dust_mite,
• infection,
• deadly_melanoma,
• aphid,
• syphilis,
• fascism,
• cyanide,
• scorpion,
• feather_mite,
• autism,
• benzene,
• deposition,
• chlamydia,
• hot_sun,
• muscular_dystrophy,
• parvo_virus,
• fungi,
• formaldehyde,
• time-bomb_dust,
• staphylococcus,
• gasoline,
• hiv,
• polio,
• slavery,
• animal,
• yogurt,
• plastic,
• salmonella,
• brain,
• dangerous_radioisotope,
• insect_venom,
• typhus,
• raccoon,
• gonorrhoea,
• insanity,
• soap,
• pointer,
• light_falloff,
• beeswax,
• soap_scum,
• phosphate,
• urine,
• combustible_rag,
• asbestosis,
• cat,
• leprosy,
• impotence,
• giardia_infection,
• shark,
• weeds,
• smallpox,
• tar,
• roundworm,
• dragon,
• meat,