Themes:
1. Grasses: fescue, crab, wheat, barley, rye, blue, oat, ect.
2. Terrain: coast, beach, atoll, reef, peak, cliff, glen, coulee, marsh, swamp, knoll, forest, moors, desert, dune, cave...
3. Stars/space: asteroid, meteor, comet, lunar, satellite, rocket,
https://en.m.wikipedia.org/wiki/List_of_proper_names_of_stars
4. Street, avenue, lane, drive, boulevard, road, autobahn
5. Ford, Chrysler, Toyota, Mitsubishi, Subaru, Peugeot, Chevy, Jeep, Honda, Beemer, ect.
6. Lion, tiger, leopard, panther, jaguar, civit, bobcat, cougar, lynx (or some other animal category)
7. Cheeses: limburger, cheddar, gouda, swiss, provalone, brie, asiago, monterrey jack, harvati, etc.
8. Numbers in the language of the country the breed originated in.
9. Black creatures: penguin, jaguar, bear, ummm...what else is mostly black? Angus cows, frisian horses....
10. There's an idea: breeds of horses.