finno

Finno is an ethnonym, which in Esperanto means it belongs to Category 1 of the country system: the people are the root, and the country is built from them. The full logic, including why some countries work the other way round, lives in Landoj kaj Popoloj.

The country is where this one is slightly awkward. The regular Category 1 form would be Finnio, and you will meet it, along with the older Fundamento-style Finnujo. But the form in general use is Finnlando, built with the ordinary noun lando instead of a suffix, on the same pattern as Nederlando, Skotlando, Irlando and Islando. Our house position: write Finnlando, recognise Finnio and Finnujo, and do not expect a rule to have decided it - usage did.

Note the double n, which is doing real work. Fino with one n is an end or a finish, from fini. Finno with two is a person from Finland. Esperanto pronounces both consonants, so the pair is audibly distinct in careful speech, but in writing it is one keystroke, and la fino de la kunveno (the end of the meeting) is a very different sentence from la finno de la kunveno.

The rest of the family is regular: finna is Finnish, la finna on its own is the Finnish language, and finnino is a Finnish woman where the distinction matters. Countries take a capital letter, peoples do not: Finnlando but finno.