Was the word ';sith'; ever mentioned in the original trilogy?

I was wondering, or was the word fabricated in the prequels?Was the word ';sith'; ever mentioned in the original trilogy?
No it wasn't in the 1977 to 1982 versions of the original Star Wars trilogy. Was the word ';sith'; ever mentioned in the original trilogy?
I cant remember if he was ever called this in the movies





but Darth Vaders full name is





Darth Vader Lord of the Sith