Aino

In the description it says that "Aino" means "my only one" in Finnish. That is not entirely true. There is a Finnish word that means "only", which is "ainoa" or "ainut", obviously close to the name, but not the name exactly. The only place where the word is written as "Aino" meaning "only" is Kalevala, which is written in poem form - with poetic license. And even that is a matter of interpretation. In general Finnish, there is no such word as "Aino", other than as the female name and Kalevala character.

Actually the word for "the only one" is nowadays "ainoa". "Aino" is an old fashioned and/or poetic way to say it.

In Japanese, Aino means 'love of'.

Originally, the character of Aino did not have a name at all. She was referred to as the only sister of Joukahainen ("...aino siskonsa"), but for some reason people thought it was her name and capitalized the word Aino, even though it originally just meant that Joukahainen didn't have other sisters.