Modifiers matching pipe:

• underground,
• nonmetallic,
• plastic,
• hollow,
• ceramic,
• metal,
• fixed,
• resilient,
• exposed,
• additional,
• industrial,
• metallic,
• inside,
• flexible,
• decorative,
• main,
• temporary,
• thicker,
• concrete,
• rigid,
• sized,
• vertical,
• standard,
• cylindrical,
• smaller,
• old,
• unusual,
• larger,
• ferromagnetic,
• conventional,
• hard,

Simple categories matching main:

• part,
• room,
• info,
• dish,
• heading,
• control,
• organs,
• food,
• elements,
• ingredient,
• cloth,
• house,
• item,
• meal,
• input,
• export,
• entity,
• wheel,
• product,
• shaft,
• appliance,
• grain,
• occupation,
• attraction,
• activity,
• thing,
• structure,
• symptom,
• event,
• attribute,
• component,
• category,
• residence,
• element,
• library,
• weapon,
• location,
• information,
• block,
• area,
• production,
• hypothesis,
• topic,
• flower,
• fixture,
• tea,
• stuff,
• focus,
• substance,
• parameter,
• memory,
• hardware,
• device,
• system,
• setup,
• profession,
• content,
• route,
• temple,
• source,
• constituent,
• village,
• force,
• medium,
• material,
• staple,
• storage,
• quantity,
• monument,
• industry,
• section,
• style,
• foodstuff,
• word,
• message,
• sugar,
• seal,
• stage,
• unit,
• axis,
• support,
• page,
• point,
• limb,
• trail,
• thoroughfare,
• apparatus,
• container,
• character,
• applicant,
• antigen,
• chemical,
• program,
• channel,
• result,
• condition,
• menu,
• frame,
• valve,
• store,
• characteristic,
• building,
• boiler,
• distortion,
• place,
• game,
• theme,
• object,
• dimension,
• commodity,
• crop,
• subject,
• fuel,
• tissue,
• theory,
• church,
• ceremony,
• window,
• nutrient,
• pipe,
• issue,
• title,
• discipline,
• module,
• output,
• institution,
• service,
• feature,
• property,
• surface,
• machinery,
• collection,
• tournament,
• pump,
• spring,
• engine,
• utility,
• hydrocarbon,
• variable,
• behaviour,
• group,
• tab,
• sector,
• process,
• cereal,
• use,
• equipment,
• package,
• data,
• circuit,
• team,
• stroke,
• document,
• facility,
• prey,
• assembly,
• assets,
• terms,
• plant,
• piece,
• festival,
• establishment,
• business,
• body,
• idea,
• development,
• article,