Satter- now Setter.
scatthold/scattales/scattholes- now scattald.
scaups/scaaps- alternative spellings of the same word, a bed of shellfish on the sea bottom.
Simbister- now Symbister.
Stenness- now Stennes.
Sullem/Sullam- now Sullom.
Thomason/Thomson/Thompson- alternative spellings of the same name.
Trosswick- now Troswick.
Urrafirth- now Urafirth.
Usiness- prob. Ustaness.