Pepysian /ˈpiːpsi.ən/ adjective1 •Of or pertaining to Samuel Pepys (1633–1703), English naval administrator and Member of Parliament, famed for his diary kept during the time of the Great Plague of London and Great Fire of London.His memoir In the Sixties (2002) sets out the philosophy of the revolution, while recording its absurdities with a Pepysian eye. — 2010 formsmore Pepysian · most Pepysian