Modifiers matching headache:

• primary,
• common,
• psychosomatic,
• chronic,
• throbbing,
• episodic,
• persistent,
• serious,
• intense,
• debilitating,
• major,
• simple,
• severe,
• secondary,
• vascular,
• paroxysmal,
• underlying,
• recurrent,

Simple categories matching primary:

• industry,
• ability,
• installation,
• activity,
• content,
• document,
• quality,
• cartilage,
• study,
• file,
• interaction,
• source,
• particle,
• disturbance,
• transformation,
• evidence,
• force,
• influence,
• characteristic,
• motive,
• coal,
• production,
• duty,
• body,
• receptacle,
• group,
• institution,
• matter,
• tumor,
• commodity,
• unit,
• antibody,
• education,
• container,
• material,
• work,
• cancer,
• game,
• waste,
• substrate,
• operation,
• code,
• reward,
• sarcoma,
• healthcare,
• trade,
• audience,
• transaction,
• fuel,
• sector,
• infection,
• residence,
• headache,
• personality,
• catecholamine,
• communication,
• aggregate,
• level,
• target,
• carrier,
• caregiver,
• experience,
• processing,
• change,
• practice,
• service,
• package,
• transactions,
• theme,
• signal,
• income,
• cause,
• event,
• diathesis,
• fire,
• loop,
• display,
• state,
• mineral,
• condition,
• product,
• member,
• standard,
• association,
• text,
• clue,
• measure,
• entity,
• kin,
• response,
• care,
• lesion,
• cell,
• function,
• utility,
• curriculum,
• form,
• offal,
• business,
• community,
• feature,
• residency,
• tumour,
• usage,
• measurement,
• self,
• object,
• alkyl,
• process,
• explosive,
• data,
• supplier,
• area,
• concept,
• meaning,
• issue,
• surface,
• factor,
• injury,
• power,
• fluid,
• drive,
• dimension,
• authority,
• signature,
• item,
• job,
• food,
• pattern,
• knowledge,
• quantity,
• substance,
• amine,
• literature,
• export,
• character,
• location,
• input,
• astigmatism,
• handicap,
• user,
• vehicle,
• radical,
• system,
• training,
• street,
• tissue,
• degree,
• neoplasm,
• rock,
• component,
• part,
• facility,
• line,
• closure,
• control,
• analysis,
• malignancy,
• desire,
• ore,
• host,
• textile,
• dermatosis,
• statement,
• lubricant,
• deposit,
• antioxidant,
• weapon,
• arthritis,
• structure,
• mission,
• law,
• aluminum,
• trait,
• deformation,
• discipline,
• fastener,
• shape,
• slide,
• medium,
• site,
• species,
• position,
• focus,
• emotion,
• occupation,
• recreation,
• relative,
• observer,
• physician,
• grouping,
• property,
• mover,
• use,
• market,
• enclosure,
• record,
• instrument,
• alcohol,
• artefact,
• fiber,
• legislation,
• works,
• equipment,
• article,
• design,
• professional,
• behavior,
• publisher,
• energy,
• intoxicant,
• actuator,
• culture,
• research,
• protection,
• ingredient,
• constituent,
• task,
• dermatitis,
• attribute,
• coverage,
• domain,
• metabolite,
• motivation,
• pollutant,
• metabolism,
• resource,
• publication,
• indicator,
• affliction,
• plant,
• point,
• organization,
• pathology,
• problem,
• conduct,
• disease,
• psychosis,
• expense,
• wood,
• obligation,
• operator,
• illness,
• metal,
• producer,
• information,
• operations,
• organs,
• hazard,
• magnitude,
• phenomenon,
• agriculture,
• disorder,