1. existing or occurring before the development or use of atomic energy or atomic weapons

Examples

• The preatomic era ended with the bombing of Hiroshima in 1945.
• Scientists in the preatomic age could only theorize about nuclear reactions.
• Preatomic warfare relied on conventional explosives and chemical weapons.
• The preatomic world had no understanding of radioactive fallout.
• Many preatomic theories about matter were proven correct after nuclear physics developed.
• Preatomic civilizations never faced the threat of nuclear annihilation.