Spencer, Herbert Syllabification: (Spen·cer, Herbert)Pronunciation: /ˈspensər/Definition of Spencer, Herbert (1820–1903), English philosopher and sociologist. He sought to apply the theory of natural selection to human societies, developing social Darwinism and coining the phrase “survival of the fittest” in 1864. Spencer, Herbert in other Oxford dictionaries Definition of Spencer, Herbert in the British & World English dictionary