Modifiers matching boundary:

• physical,
• real,
• semitransparent,
• nearby,
• natural,
• solid,
• smooth,
• jurisdictional,
• geopolitical,
• administrative,
• distinct,
• atmospheric,
• geological,
• irregular,
• horizontal,
• permanent,
• fixed,
• complex,
• hydraulic,
• moving,
• smaller,
• nonconducting,
• convenient,
• clear,
• ecological,
• hard,
• geographical,
• internal,
• simple,
• static,
• political,
• rigid,
• spatial,
• spherical,
• cultural,
• outer,
• biological,
• single,
• hierarchical,
• structural,
• oceanic,
• vertical,
• logical,
• external,
• critical,
• significant,
• crystalline,
• artificial,
• hexagonal,
• historical,
• curved,
• front,
• syntactic,
• legal,
• governing,
• visual,
• sharp,

Simple categories matching irregular:

• program,
• organization,
• shape,
• connection,
• surface,
• part,
• display,
• polygon,
• event,
• flower,
• object,
• wall,
• edge,
• road,
• payment,
• area,
• motion,
• light,
• obstruction,
• original,
• ground,
• activity,
• hours,
• dust,
• form,
• feature,
• soil,
• period,
• work,
• particle,
• material,
• body,
• organ,
• curve,
• line,
• boundary,
• border,
• solid,
• occurrence,
• behavior,
• system,
• place,
• component,
• profile,
• terrain,
• shelter,
• set,
• asterism,
• week,
• holiday,
• odor,
• condition,
• commodity,
• job,
• astigmatism,
• structure,
• cell,
• substrate,
• interval,
• array,
• pattern,
• item,
• space,
• phenomenon,
• use,
• unit,
• expense,