William St. Clair | |
|---|---|
| Baron of Roslin | |
 Sinclair, Baron of Roslin coat of arms | |
| Predecessor | Henry St Clair, 7th Baron of Roslin |
| Successor | Henry St Clair, 9th Baron of Roslin |
| Died | c. 1379 |
| Noble family | Clan Sinclair |
| Father | Sir William St Clair |
William St Clair (died circa 1379) was a Scottish noble and by tradition the 8th Baron of Roslin.