William Sinclair

William Sinclair is the name of the following people:

• William Sinclair (Bishop) († 1337), Scottish clergyman
• William Sinclair (nobleman, † before 1303) († between 1299 and 1303), Scottish nobleman
• William Sinclair (nobleman, † after 1358) († after 1358), Scottish nobleman
• William Sinclair, 1st Earl of Caithness (after 1407–1480), Scottish nobleman
• William Sinclair, 2nd Earl of Caithness († 1513), Scottish nobleman
• William Sinclair, 10th Earl of Caithness (1727–1779), Scottish nobleman
• William Sinclair, 2nd Lord Sinclair († 1487), Scottish nobleman
• William Sinclair (knight) († 1330), Scottish nobleman
• William J. Sinclair (1877-1935), American paleontologist
• William Sinclair see Willy Moon (* 1989), New Zealand musician

This is a disambiguation page for differentiating between several terms identified with the same word.