Simple categories matching harmless:

• residue,
• animal,
• plant,
• substance,
• preparation,
• creature,
• activity,
• antigen,
• material,
• matter,
• thing,
• rodent,
• liquid,
• fluid,
• particle,
• medication,
• critter,
• component,
• constituent,
• bird,
• food,
• agent,
• gas,
• prey,
• allergen,
• item,
• object,
• spider,
• impurity,
• crime,
• souvenir,
• salt,
• metabolite,
• organism,
• being,
• contaminant,
• preservative,
• neighbor,
• pollutant,
• metal,
• bug,
• solid,
• snake,
• sugar,
• task,
• compound,
• insect,
• carrier,
• drug,
• disorder,
• ingredient,
• chemical,
• powder,
• foodstuff,
• stuff,

Members with property harmless:

• hydroxide,
• water,
• chemical,
• drink,
• dust,
• nitrogen,
• antihistamine,
• military_science,
• food,
• nail-polish_remover,
• adhesive-tape_help,
• carbon,
• chlorine,
• mold,
• cigarette,
• playing_hopscotch,
• certain_food,
• white_sugar,
• regular_air,
• potash,
• flower,
• key,
• schooner_sail,
• milk,
• water-vapor_h2o,
• ant,
• hamster,
• robin,
• rabbit,
• cork,
• elephant,
• ladybird,
• market_survey,
• spider,
• deer,
• lemur,
• staple,
• shellfish,
• street_football,
• seafood,
• water-vapor_gas,
• household_plant,
• animal_dander,
• radioactive_compound,
• reading_email,
• liquid,
• cellophane,
• granite_tile,
• penguin,
• ugly_clothing,
• powder,
• powdered_sugar,
• insect_venom,
• food_constituent,
• reed,
• wood_carving,
• stew,
• paying_bill,
• vitamin,
• manatee,
• fruit_powder,
• propene,
• mosquito,
• dust_mite,
• lighthearted_proverbs,
• kingsnake,
• bicycle,
• noble_gas,
• perfume,
• stork,
• metal,
• cartridge,
• wire,
• cornstarch,
• inorganic_salt,
• soy,
• house_dust,
• jewelry,
• extortion,
• writing_exam,
• rural_development,
• evergreen_branch,
• hummingbird,
• silk_bonnet,
• pet,
• helium,
• pea,
• carol,
• yogurt,
• tweezer,
• corn,
• tweet_bird,
• pharmaceutical_compound,
• llama,
• moth,
• carpet_glue,
• toad,
• lipstick,
• beetle,
• cup_holder,
• paintbrush,
• earwig,
• lsd,
• pot,
• parrot,
• marijuana,
• dark,
• bath,
• latex,
• chalk,
• day_trading,
• child,
• cooking,
• pet_droppings,
• bones,
• dancing,
• cell,
• brownie,
• online_auction,
• giraffe,
• tranquilizer,
• cloth,
• lactose,
• cannabis_derivative,
• plywood_waste,
• bat,
• insect,
• plastic_bottle,
• plastic_spoon,
• nicotine,
• jewel,
• olive,
• walkman,
• preying_mantis,
• vinegar,
• accessory,
• button,
• aspirin,
• antibiotic,
• cream,
• scarlet_kingsnake,
• recreational_activity,
• new_picture,
• pencil,
• driver_type,
• cauliflower,
• book,
• viral_infection,
• insoluble_salt,
• pesticide,
• hydra,
• recitation,
• spinach,
• animal,
• woodlouse,
• fire_break,
• salt,
• inorganic_chloride,
• spice,
• scented_tissue,
• huntsman_spider,
• vulture,
• writing,
• cows,
• egg,
• string,
• registry_key,
• gasoline,
• reading,
• aqueous_co,
• rhubarb,
• medicine,
• beverage,
• drug,
• ibuprofen,
• pineapple,
• lizard,
• butterfly,
• baby_walker,
• cookie,
• language,
• sedative,
• potassium_sulfide,
• straw_waste,
• weed,
• dugong,
• common_salt,
• alkali-metal_salt,
• shampoo,
• co2,
• potsherd,
• cat,
• paint,
• crow,
• black_beetle,
• ballast_stone,
• open_book,
• food_ingredient,
• loose_mat,
• driftwood,
• zinc,
• urea,
• grain,
• telephone,
• statue,
• content,
• coca,
• fawn,
• hypochlorite,
• tomato_vine,
• ethyl_cellulose,
• calf,
• fertilizer,
• salt_particle,
• prostitution,
• methane,
• ethene,
• pig,
• jeep,
• light,
• oil,
• bulletproof_jacket,
• tick,
• sugar,
• starch,
• instant_messaging,
• inert_gas,
• antimalarial,
• caffeine,
• joint_advertising,
• brine,
• baby_shampoo,
• hissing_cockroach,
• tonic,
• pollen_grain,
• specific_food,
• uric_acid,
• pram,
• nail_clipper,
• stuffed_animal,
• sulfa,
• wallpaper,
• nitrogen_gas,
• doubt,
• lignin,
• paint_remover,
• balloon,
• ammonia,
• diadem_snake,
• pet_fur,
• cigarette_pack,
• air,
• cardboard,
• organic_compound,
• grass_pollen,
• small_snail,
• pan,
• animal_fur,
• peyote,
• diesel_fumes,
• fruit,
• crushed_cork,
• rice,
• songbird,
• raven,
• funnel-web_spider,
• boarding,
• sulfur,
• mouse,
• cheese,
• insoluble_sulfide,
• plant,
• grapefruit,
• thunder,
• large_ammunition,
• pigeon,
• cement,
• goldfish,
• zipper,
• plant_extract,
• ethane,
• traffic_helicopter,
• new_toy,
• new_item,
• juice,
• soil,
• wheat,
• lacewing,
• fly,
• small_cat,
• prank,
• radio,
• caffeine_pill,
• sand_boa,
• monkey,
• thrip,
• cfc,
• curlew,
• lawn_clipping,
• duck,
• dragonfly,
• helicopter,
• co,
• glass_marbles,
• turtle,
• talcum,
• box-elder_bug,
• alum,
• hydrilla,
• baby,
• vase,
• fish,
• papers,
• link_building,
• dust_particle,
• inactive_pill,
• use,
• myna,
• dog,
• tortoise,
• cat_litter,
• bird,
• aluminum_powder,
• antelope,
• blind_snake,
• heron,
• h2o,
• oxide,
• glue,
• household_dust,
• sheep,
• wallet_chain,
• mongoose,
• paper,
• exercise,
• environmental_antigen,
• felt_pen,
• aluminum,
• aerosol,
• worm,
• battery,
• open_place,
• monarch,
• dirt,
• iron,
• ball_python,
• alcohol,
• zebra,
• meteor,
• drywall_dust,
• sand,
• grass,
• leaf,
• chipmunk,
• movement,
• lie,
• sulfate,
• football,
• carrot,
• cannabis,
• satyr,
• nail_scissors,
• wasp_venom,
• starch_powder,
• stick,
• medication,
• bunny,
• yeast,
• small_monkey,
• crowd,
• wheat_protein,
• handcuff,
• meat,
• clay-pigeon_shooting,
• various_food,
• tumbleweed,
• potato,
• toy,
• inert_filler,
• bathing,
• glucose,
• dangerous_toxin,
• aged_cheese,
• smoke,
• propane,
• repetitive_movement,
• hemp,
• paper_label,
• bull-snake,
• macaw,
• semolina,
• titanium,
• newspaper,
• pollen,
• plastic_slug,
• building,
• yoghurt,
• camel,
• ethylene,
• springtail,
• dolphin,
• frog,
• mold_spore,
• closed_place,
• dangerous_smoke,
• suitcase,
• squirrel,
• dove,
• oxygen_gas,
• food_protein,
• small_dog,
• cacique,
• acetaminophen,
• nail,
• hardware,
• hydrogen,
• cockroach,
• rosemary,
• gecko,
• carbon-dioxide_gas,
• oxygen,
• jewellery,
• particular,
• ostrich,
• nitrate,
• allergen,
• food_antigen,
• christmas_play,
• thread_snake,
• decongestant,
• royal_python,
• elemental_hydrogen,
• pen,
• agouti,
• chloride,