William Plunkett

• William Plunkett (highwayman), 18th-century British highwayman and associate of James MacLaine
• William C. Plunkett, lieutenant governor of Massachusetts
• William Plunket, 1st [Baron Plunket], Irish politician and lawyer who eventually became Lord Chancellor of Ireland
• William Plunket, 4th Baron Plunket, Church of Ireland Dean of Christ Church Cathedral and Archbishop of Dublin
• William Plunket, 5th Baron Plunket, British diplomat and administrator
• Billy Plunkett, Australian rules footballer for Geelong