atom [OE] Long before scientists were able to prove the existence of atoms, ancient Greek philosophers believed that matter was made up of tiny particles that could not be broken down into anything smaller. The word the Greeks used for this hypothetical particle was atomos ‘indivisible, that cannot be cut up’. By way of Latin atomus, this came into English initially for the smallest unit of time or for an indivisible entity. The word was used in the early 19th century by the British chemist John Dalton (1766–1844) when he gathered evidence for the existence of these building blocks of matter, although it has been used in the original Greek sense since the mid 16th century, and the sense gradually morphed into Dalton’s use. A century later the physicist Ernest Rutherford (1871–1937) disproved the theory that the atom could not be divided when he split the atom for the first time in 1919. The term atom *bomb was first recorded in The Times on 7 August 1945, the day after the Hiroshima blast. Japan surrendered on 15 August, the date when the Bomb first appeared in a headline in The Times as ‘Victory and the Bomb’. But the English novelist H. G. Wells (1866–1946) was writing about an atomic bomb as early as 1914.