Modifiers matching impurity:

• physical,
• initial,
• up,
• airborne,
• unavoidable,
• heterogeneous,
• polar,
• coarse,
• harmful,
• microscopic,
• random,
• residual,
• heavier,
• mental,
• volatile,
• biological,
• mobile,
• corrosive,
• anionic,
• chemical,
• visible,
• undesired,
• sticky,
• smaller,
• absorptive,
• environmental,
• atmospheric,
• fine,
• small,
• organic,
• reactive,
• hazardous,
• dilute,
• insoluble,
• micro,
• homogeneous,
• natural,
• desirable,
• active,
• soluble,
• minor,
• gaseous,
• lightweight,
• stubborn,
• ionic,
• common,
• fluid,
• mechanical,
• unwanted,
• inorganic,
• foreign,
• little,
• colloidal,
• damaging,
• separate,
• possible,
• out,
• off,
• harmless,
• lighter,
• light,
• ordinary,
• interfering,
• particulate,
• minute,
• suspended,
• nonpolar,
• solid,
• dissolved,

Simple categories matching biological:

• material,
• irregularity,
• assemblage,
• process,
• residue,
• kin,
• works,
• age,
• motive,
• molecule,
• content,
• fluid,
• vocation,
• grouping,
• science,
• parent,
• discipline,
• membrane,
• individual,
• enzyme,
• intervention,
• necessity,
• information,
• change,
• system,
• project,
• tissue,
• contamination,
• substance,
• filament,
• defect,
• concept,
• contaminant,
• macromolecule,
• concretion,
• glue,
• mechanism,
• medium,
• scientist,
• study,
• asymmetry,
• motion,
• area,
• inquiry,
• notion,
• trauma,
• research,
• particulate,
• testing,
• solid,
• domain,
• end,
• modification,
• protein,
• space,
• disturbance,
• cell,
• activity,
• development,
• operator,
• constraint,
• organism,
• member,
• waste,
• artifact,
• pesticide,
• difference,
• amine,
• behavior,
• matter,
• disposition,
• treatment,
• carrier,
• reason,
• assay,
• component,
• aspect,
• fuel,
• specimen,
• phenomenon,
• microbe,
• profession,
• industry,
• pest,
• drug,
• particle,
• layer,
• sugar,
• response,
• relative,
• fertilizer,
• frontier,
• control,
• identification,
• polymer,
• mixture,
• therapy,
• machinery,
• processing,
• knowledge,
• integrity,
• relationship,
• object,
• product,
• criterion,
• problem,
• data,
• group,
• father,
• anticoagulant,
• invasion,
• passage,
• compartment,
• mineral,
• origin,
• item,
• technology,
• issue,
• subject,
• danger,
• ligand,
• procedure,
• character,
• task,
• nutrient,
• evolution,
• alcohol,
• trait,
• society,
• species,
• result,
• filter,
• analysis,
• marker,
• sample,
• characteristic,
• fibre,
• complication,
• toxin,
• organisation,
• nature,
• fiber,
• surface,
• test,
• interaction,
• coating,
• textile,
• catalyst,
• pathway,
• work,
• limb,
• property,
• variation,
• chamber,
• world,
• times,
• relic,
• pigment,
• terms,
• machine,
• preparation,
• signal,
• function,
• compound,
• application,
• tendency,
• shape,
• field,
• abnormality,
• part,
• attribute,
• flow,
• pathogen,
• maturation,
• means,
• insulator,
• liquid,
• chemical,
• success,
• variable,
• thing,
• lipid,
• assembly,
• activator,
• condition,
• cofactor,
• secretion,
• organs,
• disease,
• offspring,
• action,
• feature,
• event,
• phase,
• evidence,
• boundary,
• arts,
• disorder,
• reaction,
• surroundings,
• variant,
• significance,
• buffer,
• culture,
• drive,
• stress,
• antioxidant,
• anion,
• rhythm,
• ingredient,
• infection,
• adhesive,
• target,
• duct,
• fertiliser,
• plant,
• polysaccharide,
• community,
• vessel,
• solution,
• effect,
• sex,
• precursor,
• food,
• medication,
• level,
• surfactant,
• memory,
• consequence,
• behaviour,
• swarm,
• sensor,
• constituent,
• stimulus,
• factor,
• impurity,
• organization,
• quality,
• magnitude,
• force,
• aggregate,
• reservoir,
• sludge,
• fibril,
• microorganism,
• movement,
• conduit,
• passageway,
• cycle,
• measure,
• program,
• benefit,
• environment,
• damage,
• category,
• illness,
• ontology,
• sequence,
• quantity,
• network,
• resource,
• diversity,
• weapon,
• hazard,
• chemistry,
• detector,
• unit,
• substrate,
• complex,
• pattern,
• poison,
• stimulant,
• state,
• matrix,
• engineering,
• index,
• agent,
• phenotype,
• element,
• noise,
• improvement,
• creature,
• container,
• source,
• form,
• situation,
• interest,
• body,
• gel,
• brain,
• consideration,
• parameter,
• team,
• composition,
• sound,
• entity,
• topic,
• effector,
• performance,
• sector,
• appendage,
• act,
• structure,
• description,
• option,
• indicator,
• measurement,
• cause,