Modifiers matching estrogen:

• natural,
• carcinogenic,
• exogenous,
• steroidal,
• synthetic,
• active,
• nonsteroidal,
• endogenous,

Simple categories matching synthetic:

• bristle,
• pesticide,
• material,
• mineral,
• fabric,
• equity,
• grease,
• nature,
• drug,
• foam,
• fibre,
• paint,
• polymer,
• flooring,
• cloth,
• textile,
• oestrogen,
• stone,
• anticoagulant,
• graphite,
• gemstone,
• agonist,
• hydrocarbon,
• object,
• activity,
• layer,
• insecticide,
• topaz,
• latex,
• gem,
• copolymer,
• penicillin,
• chemical,
• frame,
• lubricant,
• coating,
• fleece,
• clothing,
• estrogen,
• nsaid,
• fiber,
• precursor,
• nutrient,
• part,
• event,
• fumigant,
• medication,
• cortisone,
• progesterone,
• contaminant,
• antagonist,
• lacquer,
• fluid,
• carbon,
• reaction,
• ester,
• glue,
• source,
• leather,
• intermediate,
• glucocorticoid,
• food,
• undergarment,
• hallucinogen,
• pharmaceutical,
• input,
• starch,
• elastomer,
• preservative,
• entity,
• resin,
• instrument,
• progestin,
• fertilizer,
• wig,
• flavoring,
• progestogen,
• cortisol,
• cosmetic,
• agent,
• oil,
• pigment,
• gas,
• sound,
• diamond,
• document,
• membrane,
• medium,
• papers,
• antimicrobial,
• sedative,
• androgen,
• stimulant,
• micronutrient,
• substance,
• process,
• structure,
• crystal,
• compound,
• ingredient,
• aggregate,
• product,
• adhesive,
• item,
• yarn,
• substrate,
• sweetener,
• cure,
• antibiotic,
• system,
• oxide,
• polyamide,
• peptide,
• silicate,
• insulator,
• clothes,
• narcotic,
• plastic,
• particle,
• condition,
• gene,
• unit,
• vector,
• fertiliser,
• opal,
• siding,
• antimalarial,
• abrasive,
• enzyme,
• solvent,
• glove,
• filament,
• wax,
• ligand,
• rope,
• surface,
• solid,
• amphetamine,
• anesthetic,
• gum,
• work,
• phenomenon,
• hormone,
• herbicide,
• fuel,
• component,
• opiate,
• medicine,
• corticosteroid,
• painkiller,
• antidepressant,
• molecule,
• steroid,
• carrier,
• scale,
• equipment,
• filler,
• thing,
• macromolecule,
• pianoforte,