 William Sinclair, 2nd Earl of Caithness

William Sinclair, 2nd Earl of Caithness (1459 – 9 September 1513) was a Scottish nobleman

Lord Caithness was born at Ravenscraig Castle, Kirkcaldy, Scotland second son to William Sinclair, 1st Earl of Caithness and Marjory Sutherland.He married Margaret Keith, daughter of Sir Gilbert Keith of Inverugie.