It means sir and mam, similar the the dunmers sera and muthsera. similarly, altmer derogatory word for outsiders is nerabba, and dunmers is n'wahs. Elves have their own words for things
It can't mean sir and mam respectively. Both words are used for the same player character, just by different NPCs.
Would be nice if there was like a dicitionary ingame to be found on Summerset. Especially since all the Altmer constantly tell you to learn their vocabulary...
A little help, maybe by a staff member? When I first started watching Japanese Anime in Japanese, I was rather intrigued by how the use of an honorific changed the entire meaning of a sentence. So, this is my super nerd showing, but I'm interested.