n. brother, sibling, kin

Ahrk fin Kel lost prodah, do ved viing ko fin krah, tol fod zeymah win kein meyz fundein!
And the Scrolls have foretold, of black wings in the cold, that when brothers wage war come unfurled!
(Book, Songs of Skyrim)

Qethsegol vahrukiv Hrodmir fin Krent, wo sov pah ok eruvos ahrk faraan wah Nos tum krivaan do ok zeymah.
This stone commemorates Hrodmir the Broken, who spent all his years and fortune to Strike down the killer of his brother.
(Word Wall for Nos, Cyclone)

Happy? No, I am not happy. Zeymahi lost ont du'ul Bormahu. Alduin was once the crown of our father Akatosh's creation.
Zeymahi lost ont du'ul Bormahu = “My brother was once the crown of our father”
(Paarthurnax, 0009C213)

Yes. Alduin... zeymah. The elder brother. Gifted, grasping and troublesome as is so often the case with firstborn.
(Paarthurnax, 000556DC)

A literal brother or a gender-neutral term for someone close of kin (e.g. ‘brothers in arms’).