Simple categories matching alien:

• plant,
• tree,
• material,
• pest,
• animal,
• grass,
• being,
• relative,
• genus,
• substance,
• race,
• species,
• shrub,
• beast,
• entity,

Members with property alien:

• mongoose,
• eucalyptus,
• food_dregs,
• pine,
• australian_myrtle,
• wattle,
• italian_pine,
• kudzu,
• black_wattle,
• deer,
• drug,
• gum,
• herbicide,
• dirt,
• mullein,
• honeysuckle_lonicera,
• autumn_olive,
• rhododendron,
• bass,
• terrapin,
• bradford_pear,
• dust,
• cheatgrass,
• casuarina,
• cotton,
• child,
• feed,
• syzygium_jambos,
• eucalypt,
• cactus_species,
• rabbit,
• goat,
• beard_grass,
• feral_goat,
• fish,
• big_bluestem,
• hydraulic_fluid,
• arsenic,
• cat,
• ammonia,
• cork,
• grevillea,
• brood,
• melilotus,
• poplar,
• oil,
• plant,
• pig,
• various_grass,
• sibling,
• mesquite,
• sand,
• trout,
• sheep,
• pesticide,
• spouse,
• wild_tamarind,
• cane_toad,
• australian_wattle,
• reptilian,
• united_state,
• dog,
• daphne_laurel,
• teasel,
• ancients,
• chemical,
• japanese,
• fabric_lint,
• fungi,
• ginger,
• pinus,
• gum-tree_eucalyptus,
• dandelion,
• ant,
• inorganic_mineral,
• gorse,
• lantana,
• acacia_cyclops,
• buckthorn,
• grey,
• leafy_spurge,
• camphor_laurel,
• type-a_grey,
• knapweed,
• acacia,
• gnat,
• chamois,
• agricultural_chemical,
• rat,
• australian_eucalyptus,
• prolific_mullein,
• canadian_pondweed,
• ship_rat,
• heather,
• cinnamon,
• ink,
• carp,
• small_grey,
• wife,
• banana,
• mediterranean_palm,
• minor_child,
• parent,
• aphid,
• black_rat,
• syringa,
• silky_oak,
• australian,
• west-indian_lobby,
• jacaranda,
• cereal_grain,
• lantana_lantana,
• qin,
• honeysuckle,
• gray,
• evil_god,
• tilapia,
• himalayan_balsam,
• mite_dust,
• cigar_smoke,
• smoke,
• hilo_grass,
• rodent,
• cocklebur,
• formosan_termite,
• fertiliser,
• bramble,
• smooth_brome,