Does the Spanish word hermana have an Indo-European root?

Yes, the Spanish word hermana has an Indo-European root. It comes from the Latin "soror", which itself originates from the Proto-Indo-European word "swésōr".

Here's a breakdown of the evolution:

* Proto-Indo-European: *swésōr* (sister)

* Latin: *soror* (sister)

* Vulgar Latin: *sorōra* (sister)

* Spanish: *hermana* (sister)

The shift from "s" to "h" in Spanish is a common sound change that happened with words borrowed from Latin.

Therefore, "hermana" traces its origins back to the Proto-Indo-European language, making it part of a large family of words related to "sister" in various Indo-European languages.