Category Nuances for tunnel:

• underground,
• discrete,
• important,
• concrete,
• attractive,
• social,
• wooden,
• physical,
• challenging,
• larger,
• permanent,
• visible,
• heavy,
• experienced,
• industrial,
• artificial,
• distinct,
• special,
• semipermanent,
• environmental,
• elaborate,
• hydraulic,
• electronic,
• large,
• individual,
• technical,
• complex,
• liquid,
• hidden,
• outdoor,
• narrow,
• smart,
• linear,
• closed,
• dark,
• rough,
• general,
• sensitive,
• residential,
• difficult,
• strange,
• architectural,
• noisy,
• major,
• operational,
• tubular,
• huge,
• civil,
• expensive,
• nearby,
• overhead,
• under,
• static,
• deep,
• curved,
• strategic,
• foreign,
• fixed,
• extensive,
• rigid,
• spatial,
• unusual,
• topological,
• free,
• military,
• stimulating,
• related,
• stable,
• subsurface,
• permeable,
• interesting,
• embedded,
• subterranean,
• critical,
• protective,
• urban,
• appurtenant,
• safe,
• exposed,
• open,
• inside,
• waterproof,
• horticultural,
• metal,
• underwater,
• hollow,
• long,
• commercial,
• agricultural,
• metallic,
• inaccessible,
• hard,
• absorptive,
• interactive,

Simple Categories for tunnel:

• passageway,
• facility,
• structure,
• passage,
• surface,
• toy,
• excavation,
• installation,
• hole,
• entity,
• path,
• thing,
• cavity,
• location,
• object,
• formation,
• part,
• conduit,
• artifact,
• access,
• corridor,