Simple categories matching invisible:

• difference,
• course,
• entity,
• variable,
• force,
• creature,
• property,
• disability,
• trade,
• symbol,
• being,
• microbe,
• agent,
• thing,
• illness,
• wave,
• nature,
• state,
• vision,
• adhesive,
• offense,
• radiation,
• import,
• character,
• substance,
• difficulty,
• elements,
• defect,
• power,
• quality,
• trait,
• objective,
• ink,
• symptom,
• object,
• particle,
• condition,
• level,
• process,
• substructure,
• fluid,
• ideal,
• ray,
• germ,
• diversity,
• phenomenon,
• attribute,
• item,
• structure,
• quantity,
• range,
• reality,
• energy,
• material,
• image,
• contaminant,
• matter,
• cause,
• microorganism,
• gas,
• light,
• disease,
• organism,

Members with property invisible:

• gown,
• spirits,
• history,
• god,
• absent_animal,
• alkaloid_content,
• income,
• destructive_feeling,
• subatomic_particle,
• brain_injury,
• psychiatric_disorder,
• gravity,
• meaning,
• angel,
• ghost,
• freight_charge,
• breath,
• wind,
• heaven,
• wisdom,
• common_interest,
• values,
• cat_spray,
• atom,
• suction,
• soul_cf,
• sweet_spot,
• movement,
• methane,
• prevarication,
• black_hole,
• position,
• body_oil,
• air,
• infrared_radiation,
• x-ray,
• understanding,
• universal,
• kingdom,
• hi_wisdom,
• infrared_ray,
• seminal_fluid,
• tick,
• timer_elements,
• multiple_space,
• cancer_virus,
• demon,
• meteorological_force,
• shear_wave,
• belief,
• invisible_letters,
• neutron,
• uv,
• moisture,
• health,
• meniere_disease,
• uv_ink,
• elves_ghost,
• free_market,
• platform,
• trigger,
• censorship,
• epilepsy,
• front,
• legal_blindness,
• purity,
• server,
• hydrogen,
• firmness,
• x_ray,
• cue,
• grease,
• beauty,
• neutrino,
• ms,
• livelihood_dependence,
• trademark,
• yeast,
• air_bulb,
• ultraviolet_property,
• optimism,
• breathing,
• expansion,
• oil,
• courage,
• market,
• marital_status,
• side_camera,
• tourism,
• incentive,
• ultraviolet_light,
• bugbear_assassin,
• toxin,
• space,
• ddt,
• tab,
• age,
• radio-wave_work,
• smell,
• devotion,
• idea,
• helium,
• software_control,
• invisible_book,
• social_class,
• malevolent_spirits,
• top,
• cult,
• pain,
• dust,
• emotional_impairment,
• giardia,
• mental_illness,
• electron,
• multiple_sclerosis,
• pob,
• fluorescent_ink,
• institution,
• sound,
• virus,
• magnetic_force,
• financial_service,
• heart_strength,
• justice,
• energetic_neutrino,
• motion,
• cancer,
• dark_nebula,
• process_image,
• educational_background,
• switch,
• electric_charge,
• weight,
• obligation,
• information_service,
• television_wave,
• buyer_mood,
• ordinary_infrared,
• psychological_disability,
• oxygen,
• computer,
• evil,
• energy,
• cognitive_disability,
• knowledge,
• argon,
• light,
• ideology,
• fiber,
• blood,
• emotion,
• diabetes,
• paint,
• weather,
• toner,
• depression,
• radiation,
• consciousness,
• sunshine,
• flow,
• fungi,
• time,
• bacteria,
• mold,
• temperature,
• attitude,
• organic_molecule,
• education,
• fingerprint,
• form,
• energy_pattern,
• joy,
• fairy,
• work_experience,
• legislative_intent,
• human_memory,
• variable,
• milk,
• memory_disability,
• psychic_apparatus,
• name,
• atmosphere,
• ability,
• management_function,
• essence,
• smoke,
• mite,
• utility,
• crack,
• helium_gas,
• audible_elements,
• work_style,
• attention_deficit,
• superhuman_agent,
• partial_deafness,
• deafness,
• invisible_force,
• asbestos_fiber,
• dark_energy,
• tag,
• cherub,
• disease,
• potential_field,
• lighting,
• ozone,
• freight,
• sustainability,
• infrared_ink,
• witch,
• ultraviolet_ray,
• cosmic_wave,
• parallel_universe,
• centimeter_wave,
• saint,
• sociocultural_system,
• electricity,
• transportation,
• protein_synthesis,
• law,
• pressure_wave,
• socioeconomic_status,
• event,
• divine_nature,
• dna_replication,
• spiritual_realm,
• friction,
• timing,
• arthritis,
• embedded_foundation,
• display,
• kitchen_fumes,
• magnetism,
• personality,
• love,
• microwave,
• nitrogen,
• bank_charge,
• wimp,
• cardiac_disease,
• laws,
• ancestor,
• psychiatric_disability,
• peace,
• psychiatric_impairment,
• class,
• feeling,
• particle,
• value,
• dummy,
• precious_metal,
• welfare,
• tang,
• perspective,
• devil,
• humidity,
• ultraviolet_uv,
• virtual_particle,
• mind,
• font,
• dream,
• thought_wave,
• personality_trait,
• location,
• chronic_disease,
• extra_dimension,
• powder,
• memory,
• strength,
• infrared_range,
• subcutaneous_nodule,
• parental_status,
• interaction,
• lung_strength,
• ink,
• perception,
• heat,
• current,
• hell,
• hiv,
• ancestral_spirits,
• structure,
• ultraviolet-radiation_uv,
• photo_cell,
• foundation,
• cf,
• electromagnetic_wave,
• afterlife,
• religion,
• hidden_state,
• intelligence,
• culture,
• eternal_power,
• service,
• force,
• pulsation,
• ultraviolet,
• truth,
• electromagnetism,
• hydrogen_gas,
• morale,
• infrared,
• spray,
• tobacco_smoke,
• minor_fiend,
• influence,
• satellite_signal,
• gene,
• vertigo,
• dead_relative,
• uv_light,
• psychic-energy_wave,
• sea_monster,
• thought,
• sexual_daring,
• extortion,
• air_resistance,
• power,
• motivation,
• camera_start,
• evolution,
• ego,
• copyright,
• lupus,
• hi_power,
• gas,
• infrared_image,