Meaning of ATOMIC in English

a ‧ tom ‧ ic /əˈtɒmɪk $ əˈtɑː-/ BrE AmE adjective

1 . relating to the energy produced by splitting atoms or the weapons that use this energy:

atomic power

an atomic submarine

2 . relating to the atoms in a substance:

atomic weight

Longman Dictionary of Contemporary English.      Longman - Словарь современного английского языка.